The plumpness of a boy's penis after a long session is a good measure of his jacking efficiency.
When I and my friend Bob had been jacking off together for about 6 months, we frequently discussed how many jackings produced the best results. The conversation came after we finished our session for the day, and were cleaning up. He believed that if a boy hadn't jacked off for a week or more, it would take two jackings before he could last long enough to really enjoy an orgasm. Once after we had jacked twice, and I was at home in bed, I tested his idea. I jacked slowly with my pecker lubed, and took about 20 minutes to come. He was right. I didn't have to worry about stopping and starting to avoid comming early, but could keep at it and enjoy the slow build up all the while appreciating th reddening and swelling of my pecker. When I came, it as not as violent as if I had jacked for the first time in a week when I would have shot two feet in the air, but a steady strong flowing come. This was repeated every time my pecker spasmed which happened three times. After I got down from the after orgasm high, my pecker was pinkish and pleasantly sensitive.