No reason not to do this at MW. Silva is going to be bigger than GSP no matter what weight you hold this at so no point in making him cut an absurd amount to get to 170. GSP has been working on getting bigger. A year ago he was walking around at 185-188, now he walks around at 190-193. I really thought that GSP was bulking up for Silva and they would announce that fight after he beat Hardy.
I'm a huge GSP fan but GSP says he wants to move up and that he wants to fight the best. If that is true, then there is no reason not to have this fight now, or soon at the least. Even if GSP wants to bulk up to walking around at 200, how long is that going to take when is already at 190? He has beaten everyone at WW, let's be serious there is nothing left there but rematches.
I honestly think Silva wins this fight most times, even a bulked up GSP is going to be at least 10-15 lbs smaller than Silva but cmon GSP, make this happen. Even though I think GSP will lose; the last few fights between both fighters have made me think it will be close enough that I want to see it.