I don't think that it is that big a deal shooting a bow tillered for split 3 under, in my experience. It does seem to make them a tad noisier; and perhaps some lose a little cast, but not enough to make the accuracy swap..."not worth it". Hope this helps!!
Funny thing...I've mostly shot three finger more accurately, but am experimenting with split on a couple of bows and having some surprising success
...go figure... good luck and have fun playing with 3 under!