I've noticed the same, even though I don't understand why. Do you know the science behind that, by chance? Is it just having extra energy because we're not in post-nut haze all the time, or is there some chemical element to it?
I haven't actually seen a study on it, but the guys I know that go to a doctor for testosterone jerk off as much as they can for days ahead of their appointment so they'll have low T when they're tested there. It's just a couple of meatheads but they did get what they wanted. So the theory is that not jerking it doesn't deplete the hormones you need to grow.
And back on topic, if you're not worried about body fat, it's really not hard at all to gain mass. I did 5x5's for bench, rows, and overhead press along with eating red meat and greens (and a lot of garbage) and gained enough that people I hadn't seen a few years did double takes. It's taking a long time now to lose the fat I gained though. My goal wasn't size at the beginning though, I was just trying to increase my bench. Now I'm recovering from a pec tear and like I said, it's hard to lose this shyt. I'm basically just maintaining progress I made before the injury with intermittent fasting and walking. I agree with not taking steroids until years of training. Youngsters that use it might never get their body to produce testosterone the same way again after using roids. It's sometimes a no turning back type of thing. But don't take my word for it when you can listen to a schizophrenic pimp in Thailand.