Lol, avocet8 beat me to it. This topic has been brought up so many times it has been elevated to in joke status. I just hope that lovinthebeach5 isn’t hiding under his computer thinking “Oh crap, what have I started?”
Masturbation will not affect PE gains from the point of view of hormone release or some such. I can’t discount the “plumped up” factor mentioned by matutinal_euphony for some guys. For others that can’t PE for more than 10 seconds without sporting wood spanking pre-PE might be a good thing, at least till they get used to PE. I wouldn’t see any potential problems at all for post-PE monkey spanking.
Keep in mind that spanking to excess, like 5 times a day, will take time away from PEing and give you a sore monkey.
Running a Massive Co-Front.