Fantastic. Then this is your own personal experience.
The whole purpose of PE is to achieve a healthier, larger penis while reducing the chance for injury as much as possible. It is one thing to say that warming up is not beneficial to you specifically. But why does that mean that you should then advocate it to everyone else? To say warming up is "detrimental" is just silly. It either helps you or it doesn't...it cannot hurt you, in any way shape or form. If you feel it does, please explain the reasoning behind this.
What if I was to tell everyone to start doing erect bends and uli's after only 3 weeks of PE, simply because it worked well for me and I saw some good gains. Some people would be tempted to try it, and would likely hurt themselves. Same goes with this, people just starting PE are not pros, and don't really know what the hell they're doing. Because of this they can pull a little to hard, or jelq a little to tight. Warming up gives the beginner a little leeway, and reduces their chances of having an injury...which is really the main purpose of warming up, besides increase blood flow and the fact that things stretch easier when they're warmer.