Well I don't do both simultaneously, but while I'm edging I will constantly be doing reverse kegels (anal breathing) and then when I'm getting to the PONR i kegel hard before I cum. The combination of doing both after awhile gives you much greater control over your orgasms. I like to think of the anal breathing as the
push and the regular ol' kegel as the
pull . By doing the anal breathing when edging your really forcing your body to get some blood to swell up the penis so it's nice and fat, and when you do a normal kegal your tightening up so that you cannot ejaculate.
Hope that makes sense, I'm not the best at explanations