TonyW LOL...You're strirring up too much trouble. You forgot hot and humid or cold and dry.
King, you're asking me to turn loose long distance secrets! With the same arrows 28" would have the advantage. But if the arrows were optimized for each bow, the shorter arrow will leave the bow with less horsepower but less drag. The 28" "faster" bow will bleed off energy at a faster rate so the short draw/arrow will quickly catch it and maintain what it had further. My wife taught me this, I'd have a weak arrow at my 30" draw, whack 3" off of it for her and she'd kick my butt with it. I know it sounds counter intuitive but very true.....O.L.