First off, I believe the kid is awesome and I think he is worthy of all the hype. I root for him. His interviews are even more impressive. He is completely calm, articulate and all business.
The only thing I wonder about is he continues to say he will absolutely never fight his teammate GSP. I can understand and completely respect this. But there is one problem. GSP is only 31. He has lost one fight in 7 ½ years where he ended up getting caught behind the ear. If he comes back at even 95% he is going to continue to absolutely dominate the WW division for at least another 5 years, IMO. We saw Liddell dominate until he finally hit the wall in his late 30's. Couture was winning titles into his 40's. Henderson won a title at 40 and is fighting for another at 41. The two best MWs in the world (A. Silva & Sonnen) are both past 35. Silva's dominance in the UFC began when he was 31 (again, GSP's age now) and has continued unbeaten for 6 years.
Does MacDonald think he is just going to wait around until GSP finally retires or becomes beatable? That could be 5-7 years from now if the knee heals right. MacDonald is eventually going to have to make a very tough decision. In the not too distant future the two best WWs in the world may very well both reside in Montreal and we will have a Canadian Controversy.
Perhaps he can move up to MW, since he is 6' tall, only 22 yrs old and so his body is probably still developing. I'm not sure what his other option is going to be unless GSP moves up instead, other than actually fighting GSP.
Solution(s)?
GSP doesn't need more money. Eventually, one of them will switch classes before this becomes an issue.
NONURINAUMANA - Solution is throw money at them both until they do fight. <img src="/images/phone/apple.png" alt="Phone Post" border="0" style="vertical-align:middle;"/>
Fortunately, most Canadian's value friendship and respect over "The Amerikkan Way".
^^^^^^this.
One of them can move up to Middleweight.
They have talked about switching weight classes to avoid it. Rory has said he would move to MW. Also, gap has debated it, but he doesnt really have a great frame for it. He even looked slower and too big against shields when he weighed about 190ish. Seeing as his speed is one of his best advantages, idk if mw is a smart option
Let's worry about this if/when Rory becomes the clear #2.
RKing85 - One of them can move up to Middleweight.
DING!
They have both made it crystal clear that they will never fight.
Either Rory keps growing and cannot/won't want to make that cut anymore, or GSP chases a self proclaimed goal and goes up for the 185 belt finally...
The solution (and this should happen) is GSP comes back, faces Condit, we know he defeats Condit, then moves up for the Silva fight. Not only will this make the most sense for GSP and rory, it will also make the most $$$ for ZUFFA. 
Rory will naturally move up a weight class.
Doesn't make sense for Rory to move up.
Anderson P Sonnen - Doesn't make sense for Rory to move up.
He is 2" taller than GSP with the same reach.
Like Bones, he is still developing and will be getting larger and larger if he doesn't seriously keep his caloric intake and weight training under control. One of them will move up. They are both ~195 but Rory has more room to grow than GSP.
Shrug. If a guy says he doesn't want to fight for the title, why force it? There are still tons of interesting fights for him to take. Winning the belt is huge, but it shouldn't be the one and only reason someone fights for.
UGCTT_LnPninja -I agree with you, BUT, just because he doesn't want to fight for the title at the moment, is not legit reason to move up a division. Like it was said, there's still plenty of interesting WW fights for Rory besides GSP.Anderson P Sonnen - Doesn't make sense for Rory to move up.
He is 2" taller than GSP with the same reach.
Like Bones, he is still developing and will be getting larger and larger if he doesn't seriously keep his caloric intake and weight training under control. One of them will move up. They are both ~195 but Rory has more room to grow than GSP.
^^^^ I agree with you sir. For now at least. If he beats Penn and one more contender, everyone will want to see a title fight.
Well I honestly want to see Dana force Koscheck and Fitch to fight because of all the bellyaching over that so I can't very well say that GSP shouldn't fight McDonald. I think they should if it makes sense...know what I mean?
GSP will not move up until Anderson is gone.
PR - Rory will naturally move up a weight class.I think he will have a hard time dealing with a guy like belcher
Lol Rory hype train will soon be derailed! Beating Nate, Mike Pyle, and Che Mills make you the second coming?
You all should be talking about Johnny Hendricks! Pierce, Fitch and Koscheck back to back. 
1911Bob - Actually GSP's trainer said that he might move down to lightweight. So many interesting fights for GSP there.
LMAO if you took him seriously...