One other comment, is notice of two how two dyno runs for different owners, how similar the shape of the curve is.

My opinion is that if you get a curve for similar engine types, for modern fuel injected engines and I suspect that the curves are about the same when matched pro HP peak. Ie a CRX Si curve is pretty close to the NX 2000 16 valve and the 16 valve GTI curves when you match the HP peaks. Same thing for the 8 valve golf and the 8 valve 4cyl Porche 944.

The point is,its ok to use HP to handicap the cars as long as you consider two aspects.

1) how strangled the original engine is compared to a rules limit engine. As the charts show, the Honda isn't very strangled.
2) What does the curve look like over the typical shift range. On a Honda, when you fall off the mountain, you fall a long way. Especially if you have to shift say 10% short of hp peak because its the end of a straight. These engines may put out impressive hp but the problem is, they don't make them very long!

The best of all worlds is an engine that has variable cam timing, Thats cause much less HP drop as RPM drops. Looking at HP only tells only part of the story.