If you think Lemiux beats Canelo why don't you actually breakdown why, rather than using ridiculous linear arguments that essentially boil down to "Canelo has never beaten a genuine MW, therefore he can't beat a genuine MW".
Both Angulo and Kirkland were bigger than Canelo and as big as the majority of 160lb fighters, as was Trout. He beat them all and wasn't close to being hurt by any of them. He also walked through everything Cotto had, despite genuine MW's like Martinez and Geale collapsing at the very same power.
Cotto showed a better chin than he ever has done, and that's not exactly uncommon when a fighter goes up in weight. How did Tony Bellew, the guy who got KO'd by Adonis Stevenson stay upright against David Haye, who is about 60lbs heavier and one of the hardest punchers in world boxing? I imagine the extra weight and lack of weight cut had something to do with it. I'm sure it helped Cotto absorb Canelo's power too. Although Canelo isn't known as a murderous puncher anyway, he's much more a boxer than he is a puncher.
its the way that canelo is not dominating top 154s(trout, lara, cotto) that makes me believe he wont have success at 160
sergio was clearly injured, and on the decline, before his fight with cotto and geale was in all likelood finished after golovkin as well as possibly being weight-drained.
you are correct about canelo moving up in weight in that he could become a better fighter because of cutting weight. it happens but far less than often