I guess it depends on how you phrase the answer. Certainly, a heavier bow will shoot the same arrow at a faster speed than a lighter bow, all other things being equal.
A heavier bow also gives me more options. Assuming you want a particular minimum arrow weight for hunting, say 500 grains, and you're shooting a 50 pound bow, that may be the only choice you have, as you're already at 10 gpp and I wouldn't want to go much heavier than that. With a 60 pound bow, I could shoot the same 500 grain arrow which would give me 8.3 gpp and a higher arrow speed, or I could shoot a heavier arrow and trade off arrow speed for greater penetration.