You think that I'm joking about that technique?
It seems to be pretty common amongst moto-cross racers; it's been related to me by three different people (but only one suggested the spring-annealing trick).
I admit, I have yet to actually try it. BUT, I fully-intend to use it next time I have a bike with a "soft clutch". (actually, I have one that's softening-up a bit right now, and will likely employ this method early this summer)
I'd say it's no less-valid than enlarging the openings around the pressure-plate springs. If Honda had wanted them bigger, they'd have made them so at the Factory, right?
I'll report-back on my success (or lack therof) soon enough.
P.S. Those of you who change your own tyres: If you don't have a Mojo-Lever tyre bar, WHY THE HELL DON'T YOU?!!!! That thing is FAN-tastic!