Mosley was better at 147 in reality, as he was by the end of his 135 stay very weight-drained. He was actually faster when he moved up to WW if you compare both versions, and much stronger and more healthy, according to himself as well. What made him look so much better at 135 was really one thing, his lack of opposition. He never really fought anything better than a B level fighter. He didn't even take his amateur rival Stevie Johnston, who'd have been a stern test at the pro level. He is extremely overrated at the weight for this reason.
Agreed. I do think Mosley would be a handful for a lot of great lightweights in history due to his talent and his size, but he gets overrated quite a bit at 135. His opposition was relatively weak, and it's not like he beat the best of a weak era. He didn't even beat the best lightweights at the time.