Hard resin tuck on non-hard rail

General Discussion
1

What are the performance impacts of a hard resin edge at the bottom of a non-hard rail? Below the apex, where the tuck begins. Another way I think about it is not blending the tuck 100% with the bottom and ensuring this corner is preserved with a bead of resin sanded to a hard sharp edge.

I have seen this on fish and some performance shortboards, carried over halfway up the board and then fading out.

Hypothesis is that it creates a faster planing surface when board is flat but its effects when rail is engaged are minimal. Curious to hear anyone’s thoughts.

2

Hard resin edge is for water releasing (see videos of spoon held under tap-water while running - water hugs the spoon surface when the water hits the curved/convex surface and releases/sprays when it hits the concave surface first). My Osprey Speed Demon has this type of hard edge cleverly blended into a longboard rail (almost a down-rail w/out the tuck) and it’s quite effective for changing direction - supremely responsive for a longer/bigger board. obviously the rest of the board’s design components and surfer technique/skill play a role.