imho, and in the long run, assuming a super sharp broadhead is used in conjunction with good arrow flight, then consistent arrow placement under hunting conditions will always trump a "hot rodded" arrow.
if it takes a buncha up-front weight to make a shaft fly really well, under hunting conditions, then so be it.
if the foc is greatly upped just for the sake of some thinking that sez high foc is THAT much better than low foc, and the resulting high foc arrow doesn't fly as well as the low foc arrow, who are we kidding? just looking to keep things in some measure of perspective.
the foc, efoc, uefoc, lmnop - all that stuff is ancillary to a well placed shot on game, with a good flying arrow that carries a really sharp c.o.c. broadhead.
how much better, if at all, is higher foc? there are a buncha good test that say it's definitely better. however, we all need to keep in mind that tons of game have fallen to low 9% foc arrows, and if that low foc arrow flies well and the bowhunter does things right, well, game over.
ymmv.