No way does Machida weigh anythingle less than 195 at MW. Guys like Condit, Rory and Lawler get near that weight and they're nowhere near Machida's size.
You are right that Weidman is a beast but Lyoto was clearly giving up size to him when they fought.Machida ain't a small dude. I really dont see how he makes 170. He's already really lean at 185. Weidman really is that good, Machida is probably #2 at MW.
It's possible. He has weighed in at under 200lb for a LHW fight. I've noticed that the WW fighters seems to cut a lot of water weight to get to 170lb.
Condit would be the only guy I doubt is around 195 - but he is long & lean so it's definitely possible.