Yes I do, and sometimes ALWAYS is the correct term. Just as force is ALWAYS a function of mass and acceleration, and trajectory is ALWAYS a function of velocity and g, bow efficiency is ALWAYS an increasingfunction of arrow mass and therefore,ke/momentum always ALWAYS increase as you increase the mass of the arrow. The increase may be small but it will ALWAYS be an increase. As I said before, it's fundamental mechanics. Don't take my word for it, there are plenty of books and internet sites where you can find out for yourself.

Have a great day!