I didn't notice a speed difference, I noticed a predilection to load up a bit more in the Peter fight. He was still throwing some quick jabs/left-hooks now and again, but it would have been pointless to make a strategy out of it, Peter's not bothered by that kind of stuff.
Wlad has underrated speed. A big object looks slower when moving, but that's an illusion of the naked eye, like we think a cessna is faster than a 747, when in fact it is much slower. Chambers is faster than Haye in overall movement, Haye has good isolated hand speed, but not very fast movement in general. Still Eddie couldn't land a single flush sho on Wlad. Same with Byrd who was pretty quick.
Wlad's physique has changed over the last couple of years, he seems to be more bulkier now. Which might explain the strength of his clinches and sheer power he seems to throw his punches at nowadays...
True, but Chagaev wasn't aggressive like Peter, and Chambers ran. Peter was trying to hit Wladimir, but with little or no success.