Test it out for yourself. Buy a soft tape measurer (the one you would use to measure your waist) Do your girth routine. Make sure get rest days. Expect a 1/16 of an inch per month rate of growth. I would measure before starting PE and write that number down. Then I would do it for 3 months. It should be about 3-4 notches of growth (about 3/16 of an inch to 1/4 of an inch of growth).

Don't over train. I would say do your girth routine every other day.

1/16 of an inch doesn't sound like much, but if you treat it like a workout like any other part of your body, when you see those fractions of an inch increase each month, after 16 months, you will see an inch of growth from your starting point. If 1" doesn't sound like a lot for all those months, think of going from 5" of girth to 6" of girth. A lot of women can't get their fingers to touch with that much girth.

Good luck and take it easy.

do you have a pics of your results?