I think GSP said himself his only like 187 or something around there. I remember Joe Rogan saying he walks around at like 200 which i dunno i could see it cuz he is a huge welterweight but id rather go with GSP on this one. Anyway no way his making 155... Too much muscle he would have to lose and what does he gain from it anyway?? Id rather he goes to Middle Weight then LightWeight.
Actually, he'd just have to do some major dehydrating. He's not a small WW, but not a huge one either. He's small compared to some of the bigger ones. I don't think it would be easy, but by no means impossible. I don't think he dehydrates much at all before fights.
I think he'd basically look like a smaller version of Vera at LHW.