>  the energy lost by compressing the fuel/air charge and operating
> the valve train, ... - these parasitic losses all increase
> more-or-less linearly with increasing rpm.

I believe I misspoke here.  I think the total energy to actually
compress equal masses of charge will not increase linearly with rpm,
but remain at least somewhat the same.  I'm hedging a bit
("somewhat") because the energy aspects of compressing gases in the
real world is a more hairy subject than I know how to tackle.

And apparently it works differently if you get a diabatic to do it for you. ;-)

Yours,
David