[Toolish]

Optimal launch angles for LDers are 10-14 deg, low loft and hitting up comes from the theory of lowering spin rates below 2800 rpm. It has been found through LM testing that a ball with a spin rate of below 2800 will release to its maximum on landing. Less backspin, lower launch = more run.

Worth noting that less loft and hitting on the upswing will also make for a more efficient transfer of power from clubhead to ball than a level swing with more loft...I think Wishon has proven that out, not 100% on who it was though.