Just read a post on a different site where a guy is reccomending no more than 8 strands of 8125 for 49-73#, as little as 3 strands for draw weights under 37# (loops padded to 20). I asked how he came up with these "guidelines", no answer yet.
I haven't had a problem with what I call "tiny" strings--10-12 strands of 8125 or Dynaflight '97. I don't like to go any less than that except with super light draw weights.
It's rare that you get a big difference in speed. That's not why I like FF type materials (Dynaflight '97 and Formula 8125) anyway. I like the reduced stretch and creep, and the increased durability.
I don't have a problem getting my bows quiet with Dynaflight or 8125. One small set of rubber cat whiskers does the trick. I get comments from folks all the time about how quiet my bow is.
Something I haven't noticed, but plan to experiment with, is a lot of folks are reporting that tiny FF type strings are much quieter on their bows. Some are going with 6 strands of 8125, but I won't.
My two big problems with really small strings are: Too easy to cut--touch 4-6 strands with a sharp broadhead, you are liable to get slapped out of your stand by your bow when the string blows; and the lack of adjustability. Tiny strings just won't twist up or let out much. 1/4" is about all you can get either way.
I think the super tiny string thing is a fad myself. We'll see.
Almost forgot. To get a good nock fit without padding out under the serving, or double serving, is easy. Rod Jenkins told me this trick, and it's what he does. Just wrap dental floss at the nock point to get the fit you want, then apply "super glue" to the floss and it will last.
Chad