Twang,

The class you are talking about in target is known as "Freestyle Unlimited". This class of archery allows you to shoot all the bells and whistles on your bow, scopes, long stabilizers, V bars. Tha advantage of the moveable sight verses gapping is that you are holding on center at all distances and using magnification if you want. Having the sight extended out further is a bit like shooting a long barreled rifle over a short barreled one it assists in aimming. However, the further you extend the sight the more motion you will detect while holding on. It takes a bit of practice to shoot the scope setup and every class has it own level of accuracy. I shoot both Freestyle and Bowhunter Freestyle(5 pins and a stabilizer limited to 12" from the back of the bow)classes. If you are shooting at 24 yds learn the gap distance above the bullseye and hold on that distance with your 20yd pin. It is easier to hold on a spot than trying to split the distance gap properly with the 20 and 30 yd pins. Bowhunter Freestyle(pin) shooters can shoot right up there with Freestylers there is not a large difference in the scores at the higher competition levels especially at short ranges like 20-25yds.

Hope this helps to answer your questions