Why would you need to walk the string at a OSTA shoot when the farthest target is only 30 yards? String walking was very popular back in the days of field archery when they were shooting a lot of 40,50and 60 yard bullseye targets. I'm talking the 1960s and early 70s. That was back when the bows of that era had a lot of arc in archery. These modern bows shoot so flat even the 40lb bows I don't see a need for it. That being said I don't care how you choose to be shoot!!! As far as not being traditional string walking as been around longer then most of us have been alive. I first heard about it back in the 80s. From guys that did it in the 60s. A archer still has to do his fundamentals correctly to kill the target IMO. What works for each individual is all that really matter in my mind. It should be fun and killing the target is a lot my fun for myself
String walking is still popular. It's used in IBO World Trad shoots and the Vegas Indoor Bare Bow class shoots.
My "point on" is 30 yards with the bow I'm shooting. Everything inside 30 yards requires me to walk down the string to change the point of impact. Otherwise, I'd be gap shooting, which can be done, but it's more of a guesstimation than an exact known.
Using the marks on a tab or marks on the string itself, allows for the changes in trajectory of the arrow, which works similar to sight pins....but they're not used as aiming points, they're reference points.
I used to use an instinctive gap method, where I could see the arrow in my peripheral vision, but used the gap between the target and the tip of the arrow as a reference. It required a lot of range time to keep it fresh in my mind and it wasn't consistent. In a controlled environment, like 3D, it has some benefits. In a hunting situation, where things can change without notice, I'd rather rely on a more consistent method like string walking.
The black mark on my tab is the reference point that I place on one of the yardage marks. The bottom green serving tie is 15 yards, the red one is 20 yards and the top green serving tie is 25 yards. Up against the arrow is 30 yards.