What's the smartest defense against someone who jumps guard while standing and manages to grab a guillotine on you. I'm assuming that it's smart to stay standing to deal with it rather than follow him to the mat, but what then?
I prefer trying to go down with the guy and try to get side control right away. You can also drop back and focus on the hands on your neck. Not the best for points game but if you know the guy is really good with the guiliotine it might be your best bet. Trying to stand and hold the guys weight can work. I have seen a few guys blow out there knee trying to support their opponents weight from a jumping guiliotine so be really careful and drop down when you need to. getting taped is much better than blowing out you knee.
TazPlex 
Seriously though, I would say protect the neck and tuck your chin as much as you can. If you must go down, control it as much as you can and try to pass to a von flue.
If you can stand straight up and posture UP.
Imagine you are trying to do a duck under.
When his arm is high like that its's pretty isolated and not as strong as it needs to be to finish.
If he manages to break your posture, your gonna have to go to the mat. Get your fingers inside the choking hand. Palm facing your chest (like a barbell curl) reach your other hand over his shoulder and smash.
KEEP YOUR HEAD OFF THE MAT AT LEAST UNTIL YOU GET THAT GRIP!!
If it's a marcelotine tap out. :)
If it goes to the ground i'd probably get his wrist with one hand, tripod up on my head and toes to relieve pressure, and cross face all my weight on his throat with my forearm while fighting his grip. Usually works. Haven't been guillotined in a long time, though.
My best defense is trying to not getting stuck in it in the first place.
This reminds me of Renzo vs Miletich
robhustle - This reminds me of Renzo vs Miletich
Longest guillotine ever!
Shields and Lawler comes to mind, too.
jw234 - What's the smartest defense against someone who jumps guard while standing and manages to grab a guillotine on you. I'm assuming that it's smart to stay standing to deal with it rather than follow him to the mat, but what then?Check this out:
Same side arm as their choking arm - grab a monkey grip on their forearm/wrist right are the most pressure is.
Other arm - hook it over their other shoulder tight to the elbowpit with enough tension that you can jump up and hold yourself up with those two grips and their guillotine grip.
It's next to impossible for them to finish that way if you keep the proper pressure on those grips and jump up and tuck ur knees in front of them - not around them
I'm with uberpinscher but I'd also take them to the ground and tripod, smash their face, and shimmy out
uberpinscher -jw234 - What's the smartest defense against someone who jumps guard while standing and manages to grab a guillotine on you. I'm assuming that it's smart to stay standing to deal with it rather than follow him to the mat, but what then?Check this out:
Same side arm as their choking arm - grab a monkey grip on their forearm/wrist right are the most pressure is.
Other arm - hook it over their other shoulder tight to the elbowpit with enough tension that you can jump up and hold yourself up with those two grips and their guillotine grip.
It's next to impossible for them to finish that way if you keep the proper pressure on those grips and jump up and tuck ur knees in front of them - not around them
If I'm reading this correctly they haven't jumped guard? They are standing and you are are posting up on them to relieve pressure, yeah? I do this, though it doesn't apply to the OP
Work on your posture from the tie up. Don't let someone snap you down to a guillotine. If they can jump guard into guillotine then they can easily front choke tie up, sprawl and take your back.
JohnnyBrabo -Yeah sorry ur right like if they catch you standing or somehow the dead end is standing - arm over their should and other hand on their choking wrist, then hopping up and make them carry you with everything tight, arms t-rexed, etcuberpinscher -jw234 - What's the smartest defense against someone who jumps guard while standing and manages to grab a guillotine on you. I'm assuming that it's smart to stay standing to deal with it rather than follow him to the mat, but what then?Check this out:
Same side arm as their choking arm - grab a monkey grip on their forearm/wrist right are the most pressure is.
Other arm - hook it over their other shoulder tight to the elbowpit with enough tension that you can jump up and hold yourself up with those two grips and their guillotine grip.
It's next to impossible for them to finish that way if you keep the proper pressure on those grips and jump up and tuck ur knees in front of them - not around them
If I'm reading this correctly they haven't jumped guard? They are standing and you are are posting up on them to relieve pressure, yeah? I do this, though it doesn't apply to the OP
Gotta be careful doing that, though. They can unclasp their hands and use the non choking hand to wrap around your back and take you down pretty easily. Especially if one or both feet are off the ground at the time.
Hasn't happened to me yet when using that defense but it could. Food for thought.