Can't beat that 110 pound weight advantage of a 400 vs H2 and narrower frame with potentially higher corner speed.
I'm not finding a comparison between corner speed and segment time of MotoGP and Moto3 (250cc) on Google, but I've read about it years ago. That's proprietary information. It's like 2 ton NASCAR Cup cars are never compared to Modified and Late Model cars which are lighter and faster, at least on short tracks. It's embarrassing.
My old home circuit at Silverstone England proves horsepower is important when there is no speed limit, and size of tire contact patch: