Not a lot of training threads these days so I figured I'd contribute a little.
I've read a couple things lately that you might find interesting. Postactivation potentiation says that if a compound lift follows a power lift, the trainee will be able to commit more power to the compound movement. That is to say, hang cleans done before back squats can be beneficial to your squatting.
It even works for endurance athletes!
As for the science right now, this is a physical phenomenon, which means that we don't know the exact reasons that this happens. Research and anecdotal data so far have proven for it to be true.