Nice interesting pull shot theories.
Down here in Florida, pullshooters try to emulate Horton and Yore, among many other pullshooters that have been shooting their screaming shots without stressing their bodies after 23+ years on the PROMASTER and OPEN events and many many titles.
Clue#1: A screaming pullkick seems to travel more than twice the distance in the same time without needing any additional "Recoil". And having even more lateral speed! Of course any two-player shot is harder to master and time.
Clue#2: The best pullshots seem to have a visible, "slow" beginning, but seem to disappear after the first half inch of travel or so.
Pros and ProMasters who have survived over two decades of intense open competition shooting use hardly any "Recoil". They predominantly use extremely smooth, accelerating "Pitch" or "Toss" takeoffs on the pull. The effectiveness of this combination of longitudinal and lateral spin can be easily proven. Prove it to yourself by having a friend at a bowling alley throw a ball while you stop it within the first 6 feet past the foul line, and then again by putting a hand on it anywhere 3/4's or further, down the lane.
Longitudinal roll, or siderolling speed, uses acceleration to get to much higher lateral speed than any caveman "yank" without any "tell" or indication at the "Pitch" or takeoff. This leads to the optical illusion of a pulled ball being visible the first half inch or so, then disappearing, leaving no obvious "jerk" or other "tell" for a goalkeeper, especially a racer, to use as a signal to jump to the 3/4 or long. If a pullshooter has ever had the problem of the pulled ball outrunning his/her 3bar player at the release or firing point, leading to a chip or edge shot to the corner, or a stub, then you know how powerful the lateral acceleration speed can be. But duffers usually try to "punch" or recoil the shot into a square, instead of using physics and just timing their player to touch and follow the ball correctly.
Lateral spin, parallel to the surface, accelerates its spin even faster, and with timing practice, is used to counter the pulled ball's momemtum trying to force itself away from the goal at release. This is comparable to a basketball layup shot straight up to either side of the basket, using lateral spin to "kick" the ball into the basket. Of course, to get the full effect of the "kick" the shot must be stroked to stay on the ball and actually follow it at release. This is the real reason for the return motion seen on a correct pullshot, and NOT a brute return motion "punch" which sends most of those who practice this into retirement, or to switch to a rollover.
Starting with ball closer to directly under the rod gives more lateral spin, allowing much harder striking of the ball for 3/4 and long and beyond deadbar releases. Starting with the ball further back has the lower tip of the 3bar player's foot closer to the middle of the side of the ball, and results in a mix with more longitudinal spin and acceleration for lateral speed. This use of angular acceleration to impart both higher lateral speed and the squaring "kick" takes advantage of physics without stressing any portion of the hand, wrist, elbow, shoulder or any part of the physique with any caveman "Recoil". Most pullshooters find a good medium between longitudinal and lateral spin at takeoff. With more practice, one can even easily shoot pulls beyond the deadbar, and repeat it for hours without your arm falling off. We play that "dollah-dollah" game with the NEAR 2bar set at half a man past deadbar. It separates the correct pullshooters from the cavemen who will eventually switch to a snake after they see their orthopedic surgeon.
In addition, of course the shooter should find a relaxed position which allows minimal energy and comfortable shifting of body weight and arm during the shot. But the cranking caveman pullshooters have been so easily outlasted by snakeshooters who stand whichever way they want, comfortably and all week during an Open tournament! I dare any, especially Robert Uyeyama to use his recoil shot and compare it to Todd Loffredo's monster superlong pull while standing on one foot with the other leg crossed. There will always be racers who can beat any yanking pull shot with hardly any spin and only able to shoot a square at best. And wasting all that energy pounding to square that ball, for nothing.
I've seen Todd, played back for Tom Yore, against R. Wight, Mike Cody, Beine, and seen Murray, and Tracy Mc, and there is none of that "Recoil" or "Whip" crap. Most are comfortable wrist initiated pulls with a hammer grip that hardly move the elbow more than 2 inches or so! Watch Ezekiel "Zeke"'s demo on YouTube on pullshots, and check for any monster "Recoil" or "Whip" motion. The old 1980's pullshot technique has done more harm and caused more retirements than anything else. I thank the emergence of the snake for the alternative for all these great players to continue, and the emergence of the Euro to show that correct technique with practice and dedication is what matters, not the nature of the shot.