Urchin,
It may not be a reduced performace change that Pyro has in mind. There are a lot of things that could be adjusted, some would help it and some would hamper it.
If I were to guess though, I say the adjustment will have something to do with it's stall speed and extreme low speed handling being too good right now. It could also be a small bumb in speed, though 1mph to 2mph off the intended speeds doesn't usually get attention.