Why do you think it would be a benefit anywhere? It is a neat-o sounding mod but unless you need to hit a certain corner on a specific track a certain way that requires you to shift at an exact point where this is the only option, I don't get it. Not every rider at the top of the sport used this pattern.
Coming into a corner hard, your body is forced forward, and it is natural to step down on the shifter as you move there. You are also stepping down on the rear brake, mirroring the action. Same with acceleration, pulling up as you might get forced back, (not on the 300 but you get the idea) is natural.
Secondly, jump on someone else's or your own different bike and destroy it as your muscle memory is all opposite? No thanks.
Coming into a corner hard, your body is forced forward, and it is natural to step down on the shifter as you move there. You are also stepping down on the rear brake, mirroring the action. Same with acceleration, pulling up as you might get forced back, (not on the 300 but you get the idea) is natural.
Secondly, jump on someone else's or your own different bike and destroy it as your muscle memory is all opposite? No thanks.