(This isn't aimed at anyone on this board, it's a rant over discussions I've had elsewhere. I also have questions at the bottom)
Maybe this is a small thing to get my panties in a bunch about, but that's what im good at. Had arguments, had discussions, done math, had others do math, put in a lot of thinking time, and am still coming to the conclusion that moving forward or backwards to carry a pin is antiquated, illogical, and a complete placebo. Let's look at the math first.
Assuming a common house shot line of a release on the 18 board, with a breakpoint target of 5 at 40 feet (a line that also makes the numbers rather generous), moving back 6 inches on the approach (also assuming you're a robot with laser precision) changes your launch angle a tenth of a single degree, resulting in you placing the ball down in the neighborhood of 3/4 of a board right, or appx the 17.25 board. Considering that moving back on the approach doesn't magically make the pattern shorter (which really got the panty bunching started, completely illogical), even if you were laser precise, ignoring ALL other factors, this move is completely insignificant and astronomically dwarfed by the standard deviation of human consistency.
The belief that moving back 6 inches will get the ball to roll/hook 6 inches earlier is . . interesting. It really depends on what the ball roll is doing in the first place. If you're leaving flat 10s because your ball is rolling too soon and bleeding energy, moving back 6 inches would theoretically cause the ball to roll even earlier and bleed more energy. Factoring in the coefficient of friction, something that has more to do with when a ball rolls and hooks than anything else, 6 extra inches in oil amounts to what gained? Because most people lay the ball down at varying places past the foul line, you could either be adding 6 inches of oil (for example, if the pattern is 40 feet long, and you normally lay the ball down a foot past the line, resulting in the ball traveling through 39 feet of oil, if you back up 6 inches, you're just making the ball travel through 39.5 feet of oil now) or if you lay it down early, you could be adding 6 inches of dry, unoiled approach BEFORE the ball gets into the oil, something that could change the trajectory of the ball.
The effects that moving back ACTUALLY has? Depending on how many steps you take, it could add 1-1.5" inches per step to the length of your approach on average obviously, and that's only if you intend to end up sliding in the same place. If that is the intent, or the result you're going for, the move is absolutely irrelevant, ineffective, and insignificant. However, if the intent is to make your steps longer or speed your feet up, depending on the current quality of your timing, that could help or it could hurt. Walking faster or slower can change all manner of things in your timing which add MANY more variables which result in more changes than just getting the ball to roll 6 inches earlier. If THAT is the case, I have no idea why someone would want to use their entire body and slightly alter many different mechanics to achieve something that a much smaller, more localized adjustment could fix.
To me, after looking at the logistics of it, it's an old antiquated idea along the lines of angling your thumb back to get a cleaner release. It's a basic random thought that will drop into someone's mind that sounds plausible at first, but upon further examination really falls apart. It's into the placebo realm, it's tricking your mind into believing something simple will fix a problem, which makes you more comfortable and relaxed, more often than not resulting in a better quality shot. Because I can guarantee you that if you back up 6 inches on the approach, you won't throw the same exact shot next time, you won't end up exactly 6 inches further back on the approach, or if the intent is to add length to your steps, you won't end up exactly where you normally do. You know how many repetitions you need to change a mechanic, or how many times you need to do something to erase old muscle memory and create new? And you really think this is going to work perfectly the first time? What other mechanical adjustment have you ever learned that worked the first time? This reduces the reasons it would work to being placebo or coincidence.
Anything I missed or left out or didn't consider?
