I have had no problem with a B50 string on my main bow for 12 years. The edges are rounded nicely and sanded to a fair-the-well. As for building them up, yeah I suppose you could do that, too. Adding extra weight at the string or worse yet at the tips is the last thing I would opt for. Lotta ways to skin that cat, and most of the different choices are not going to make drastic problems. the difference in arrow cast from a 12 strand B50 versus a 10 strand is not going to make or break a 20 yd shot on a deer.