A cup is an aid. An efficient submission requures you to remove as much slack as possible. You cant say that forming a rigid base to apply force againsst isnt an advantage.
A cup also is painful when someone is back mounted, sometimes for the passer, etc.
I get irritated by my partners cups.....funny thing is, im sure theyd shit themselves if I started wearing one.
The IBJJF bans technique after technique for rare or unconfirmed injuries yet something as simple and highly effective as a cup to protect one's reproductive abilities is deemed illegal. It's a machismo thing and little else.
While I certainly believe some people have the physiology to support cup-free grappling, for those who are more well-endowed or whose testicles do not adhere (or do not adhere tightly) to their scrotums, this is simply a game of Russian Roulette with their anatomy.
Well I am asian
ColeMillerATT -checkuroil - If your cup causes you injury then you are not wearing it correctly If it shifts then you may be wearing the wrong size.This...I wear a cup to every session. The days that I do not wear one I get hurt. Guys are really heavy with knee passing. Triangle chokes the guys immediately use knees or forearms if they kind of have their second arm 20% still in to pry themselves free. Attempting armlocks and knee bars hurt the practitioner often when not wearing a cup.
Pur the supporter with the cup on first. Then put compression shorts over it.
Do not buy the compression short cups. They shift everywhere. Buy the jock strap supporter and put the compression shorts over them
Perhaps it does aid in getting submissions, but that is because the appliers nuts are still attatched.
The major organizations allowing the 50/50 knee reap, grabbing the inside of the ass of pants ,yet not allowing cups or twister position is retarded. They just look like idiots to me. Last night I would've been in the ER if I didn't wear a cup with the aggressive knee slide attempts of larger opponents.
yeah, wtf is up with the pants grabbing inside the belt line? Last nigth I had a guy doing this with his fingers inside my underwear straight yanking that shit down while trying to stack me. I was waiting for my bibs to get down below my ass cheeks so I could roll back into his face and lock up sweaty asshole submission.
I did the first 5 years bjj no cup. after getting repeatedly knee cut across my nuts I found the jaco compression short version. try it and thank me later.
Don't know, it's a rare occasion I get the balls racked at bjj practice. 
ROFL Deserves a ROFL copter if anyone has a cut and paste.
Tomato Can - Actual dialogue I had at my first IBJJF tournament just before my 1st or 2nd match:
Me: Wait, I can't wear a cup?
Referee: No, if you're wearing one you have to remove it.
Me: But ... my balls. What about my balls?
Referee: You must use jiu-jitsu to protect your balls.
http://fc08.deviantart.net/fs22/f/2007/342/1/f/ROFLCOPTER_by_Yoshio_the_Hedgehog.jpg
I've never worn a cup to jiu jitsu in 8+ years and I can count ball injuries on one hand (knock on wood). I've seen people wear cups, get complacent, then if they can't have them or take them off they don't really know how to keep themselves safe. I've also been hurt from people wearing cups way more times.
But I don't care. If people wanna wear cups that's their business. I prefer not to, and just like really snug underwear/compression shorts. I'm not gonna bitch and moan if someone wears a cup.
knee smash - i never wore one and i don't rely on a cup to protect my nuts, i rely on myself
THIS
If people try knee through the middle I move my hips to protect my balls. Cups should not be allowed. They are a weapon.
Your first nut injury could be your last
Tomato Can -I've gotta say I disagree. There is a massive difference between arm locking some one with a cup on and one without. You have only got to think about the space the cup occupy's between your hips. Not only this when taking the back it is dangerous. Creates unnecessary pressure on the spine.Soul Gravy -CraftyHobo - Lol, have you never competed before?
A groin cup can be a more brutal fulcrum for armbars
If you're deep enough into an armbar that a cup matters, odds are a good guy is going to finish it anyway. I've never bought this excuse.
I've always felt the same way. It could make a difference, but it's a pretty small one.
ILS, where did you hear that about FILA wrestling rules? I checked the rules and I can't find any mention of it:
http://www.fila-official.com/images/FILA/reglements/olympique/Wrestling_Rules_July_2014_Eng.pdf
Just use a generous amount of bubble wrap. problem solved.
ozjiujitsu -Tomato Can -I've gotta say I disagree. There is a massive difference between arm locking some one with a cup on and one without. You have only got to think about the space the cup occupy's between your hips. Not only this when taking the back it is dangerous. Creates unnecessary pressure on the spine.Soul Gravy -CraftyHobo - Lol, have you never competed before?
A groin cup can be a more brutal fulcrum for armbars
If you're deep enough into an armbar that a cup matters, odds are a good guy is going to finish it anyway. I've never bought this excuse.
I've always felt the same way. It could make a difference, but it's a pretty small one.
ILS, where did you hear that about FILA wrestling rules? I checked the rules and I can't find any mention of it:
http://www.fila-official.com/images/FILA/reglements/olympique/Wrestling_Rules_July_2014_Eng.pdf
Again, if someone has gotten far enough into an armbar that the cup is helping, he's most likely going to finish it anyway. Blaming the cup is a shortcut to admitting you got caught in the armbar to start with.
thebigkahuna -knee smash - i never wore one and i don't rely on a cup to protect my nuts, i rely on myself
THIS
If people try knee through the middle I move my hips to protect my balls. Cups should not be allowed. They are a weapon.
I never rely on a helmet to protect my skull, I rely on myself.
I never rely on a seatbelt to protect my body, I rely on myself.
I never rely on a lifejacket to keep me afloat, I rely on myself.
See how that goes?
"A cup also is painful when someone is back mounted, sometimes for the passer, etc.
I get irritated by my partners cups.....funny thing is, im sure theyd shit themselves if I started wearing one."
So is being crossfaced. Having a guy on top of you in knee on stomach. Having a guy knee cut across your thigh. Much of BJJ is uncomfortable. A cup is no worse than a lot of other stuff already going on.
I don't wear one, I don't care if my training partner does or not. Accidents happen on occasion, yes. Besides, my plumbing has been snipped. I'll take my chances.... 
Soul Gravy - "A cup also is painful when someone is back mounted, sometimes for the passer, etc.
I get irritated by my partners cups.....funny thing is, im sure theyd shit themselves if I started wearing one."
So is being crossfaced. Having a guy on top of you in knee on stomach. Having a guy knee cut across your thigh. Much of BJJ is uncomfortable. A cup is no worse than a lot of other stuff already going on.
When a partner arches while back mounted and the cup bites into your spine is that a legit attack compsred to a crossface, etc? We all know how to do "dirty" shit to make life harder or get a cheap tap in training, but we dont do it. A cup can be used purposefully 9r inadvertantly to cause pain and injury and like a brace with rigid structure should be avoided if possible ,with the exeption of protecting and injury.
A couple months ago i ciuntered an armbar......all was going well but the cup bit deep into the tendon and muscle area below and outside my elbow so I tapped. I dont care that I tapped, but what pissed me off is the pain and inflamation for 2 weeks negatively impacting traing and working out. Without the cups presence, I would have worked through my counter and continued doing whatever we were doing.
So with that particular partner i could prevent the chance of mild to moderate injury and pain simply by shutting anything down, dont let him get my back, etc or just not train with him. What benefit is gained by either?? I coukd easily do more damge to my opponents due to my size and explosiveness wearing a cup......but what woukd that accomplish?
Tap early if you're worried about the cup damaging your arm. Personally I make it a point to tap long before a cup becomes an issue--no point in trying to fight out of a submission I know I'm caught in. It sounds like you waited too long to tap. If your training partner is intentionally digging his cup into you in painful places, that's a training partner problem, not an equipment problem.
"So with that particular partner i could prevent the chance of mild to moderate injury and pain simply by shutting anything down, dont let him get my back...."
This is what jiu jitsu is. You should be trying to shut him down and defending against the back take regardless of whether or not he's wearing a cup. Or if you're that worried about it, as you suggested, simply don't roll with him. Just as you feel you shouldn't have to sacrifice your safety and comfort for him, he's under no obligation to sacrifice his for you.
Soul Gravy - Tap early if you're worried about the cup damaging your arm. Personally I make it a point to tap long before a cup becomes an issue--no point in trying to fight out of a submission I know I'm caught in. It sounds like you waited too long to tap. If your training partner is intentionally digging his cup into you in painful places, that's a training partner problem, not an equipment problem.
"So with that particular partner i could prevent the chance of mild to moderate injury and pain simply by shutting anything down, dont let him get my back...."
This is what jiu jitsu is. You should be trying to shut him down and defending against the back take regardless of whether or not he's wearing a cup. Or if you're that worried about it, as you suggested, simply don't roll with him. Just as you feel you shouldn't have to sacrifice your safety and comfort for him, he's under no obligation to sacrifice his for you.
I wasnt caught.....my elbow was rotated, past and safe. His effort to keep it/get it back dug the cup in. It happens....he was work8jg for a sub and I was working counter.
LOL@ "This is what jiu jitsu is. You should be trying to shut him down and defending against the back take regardless of whether or not he's wearing a cup."
Training involves give and take as well as domination. It also IMO involves a lot of hard position sparring for repetitions and focusing training. He is a good, technical, brown belt......a bit naturally aggressive, but not over the top and very considerate and friendly. If I smash him and shutdown everything and give up nothujg......how does that benefit me and him or everyone else?
i trained the first 5-6 years wearing a cup every single time i trained. then switched to a gi school where no one wears one as they are IBJJF heavy competitors. It was strange at first but now i've gotten used to it. That being said i never once cared about someone wearing a cup and prefer that everyone did in training and competition.