Depends.... If you are going for length- it is better to jack off quite often. Well, DLD did not say it like that, but I remember (and checked the thread yesterday) a thread of DLD where he mentioned that the post masturbation stretch is the best stretch you can provide. I can link you the thread if you want
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When you're going for girth- you want max EQ (or at least as good as possible). If you masturbate (ejaculate) often- you'll have weaker erections. But if you choose to abstain yourself from ejaculation- your libido will be much higer!
Hope I helped- if you need any additional details or have any other questions- hit me