.....compound shooters can get away with it not being right in the ball park, we cannot.
I'd have to disagree, at least to a point. The reason being I see guys shooting carbons with 100 grain inserts and 160-200 grain points with no problems. They need the weight to get the over-all weight up and the spine down. Couldn't say if it would work as well with wood or aluminum, but it does work with carbon.
I have no idea what my FOC is, but I get great flight. I shoot a 125 grain point with full length POC (31.5" approx.) that usually weigh 600-650 grains (finished arrow).
Chad