You're correct about the center serving. It can slow things down if it's excessively long, but only by a few fps. The purpose of center serving is to protect the string from wear by your fingers or release---not from hitting your arm or clothes. Adjusting your draw length and/or grip will take care of that.

That being said, for a couple years now I have cut down on cneter serving length to about 3-3 1/2". If you shoot a loop there is no reason to have it any longer. Your string doesn't need protection from the release because the release doesn't contact the string. Basically all you need is enough to give the loop something to grip and enough that it doesn't slide around on the string.

Serving near the cams has much less effect on the bow's speed. I keep it to a minimum just for the purpose of being able to use my Leeches like speed balls---close to the cams themselves.

As for serving in the peep and kisser? Well, I don't use a kisser so that a moot subject. As for the peep? I've learnedover the years that if strings are made properly they are long enough that they can be twisted so there is about one twist every 1 1/2" of length. This is plenty to allow me to install a Specialty Super Ball or Fletcher True Peep without serving it in. The string is actually tight enough on both sides that serving isn't needed. So far I've never had one move on it's own. Infact I have a hard time moving it intentionally.

Another trick is to pick your strings made from lighter materials in the first place. That's why I have been using BCY 8125. It's maybe 3 fps faster than some other materials.

So how much speed does this give me? Totalled up about 3-5 fps. Not much really, but a couple here and a couple there and pretty soon it can mount up to about 20 fps over most peoples' setups.

I am aware that speed isn't the end all of archery. Accuracy is, but why worry about getting a fast bow and light arrows to gain more speed if you intend to choke down the available speed with unneccessary accessories.