Art,
Actually Cougar adding 60grs will likely take a bit more speed than that......
I' ve been doing a lot of informal testing of arrow speeds with respect to heavy and light shafts, and most of today' s hard single cam bows lose about 1fps for every 2.5grs of arrow weight added.......that would mean he' d lose about 24-25fps for that 60gr increase on his Martin.
Some of the real hard duals are closer to 1fps for every 3grs +/-. but most likely his set-up is closer to double what you said.......doesn' t really mean a hill of beans at 20 yards but I thought I' d throw it out there.

For example my Patriot Dually which is a rocket of a bow shot a 474gr arrow at 289fps......a 374gr arrow at 319fps. That' s a 30fps difference for a 100gr increase. 1fps for every 3grs.

I think the good mid-weight carbons and A/C/C' s are nice alternative to the more fragile aluminum equivalent. (Although the A/C/C' s are a bit expensive of course they have proven cheaper in the long run for me just because of how much more abuse they will take Vs. Alum.....I actually killed 5 deer with the same shaft) The new Easton Axis arrows should be interesting......they sound sort of like an all carbon alternative to a shaft similar to the A/C Kinetics in weight.