All I can say is...it's worked for me for decades.
The reason I went from a relax trigger release back to leather tab and three finger solid grip, is that it provides a great balance between holding the majority of the weight with the middle, ring, and pinky fingers; while providing the thumb and index finger with enough tension to assist in 'aiming' and timing the release of the shot. Here's a pic of forum member, Pancaker, holding one.
The best relax trigger unit I tried for slinging heavy ammo was made by TruFire, which was an archery release that activated on either pull or release.
With today's CNC tech, one could get very creative with this concept.