P.S. How I proved voltage doesn't make squat of difference, is I was trying out the local shop's CE4's, which were coiled great and tasted great, and I was turning the voltage completely up and down on their battery, and the CE4's did great at 3.3V's, did great at 4.8Vs, believe it or not. When you first take a puff on a device, if the coil is wrapped well, it'll taste GOOD, with no wicky tastes, with no downtrodden tastes, at any voltage. If not, it's a sign that it's a bad coil, to a certain extent, or a bad juice. In my testing, I seem to prove that voltage rarely has much of a needed effect in either direction beyond 3.7V's.
Voltage makes a huge difference. Many people can easily taste/feel the difference between 4v and 4.3v, because they have actual, extensive, real-world experience using this equipment, You know the reason you could turn the voltage all the way up, and all the way down without issues? Because it's an eGo twist. It's weak. The CE4 was probably 1.8ohms or something, so the ego's limit kicks in with the voltage up, so adjusting the voltage basically does nothing.
Your testing doesn't prove anything because it's incredibly flawed. You used a few pieces of cheap low end equipment and then based on that experience you make absolute far-reaching statements about other equipment. You say voltage doesn't matter, because you couldn't detect a difference using one specific setup. Not realizing that the setup probably wasn't even delivering the voltage you thought it was, and is the least capable variable voltage setup on the market.
Your testing is similar to if I "proved" that cars cannot go faster than 100 MPH because I was in a slow car that wasn't capable of reaching 100MPH. Then going around talking with authority that cars can't go over 100.
Get a "real" variable voltage device. Get something cheap like a vamo. Put dual 18350s in it. Set your voltage to 3.3, then set your voltage to 6v and tell me there is no difference. At 3.3 you'll probably get a decent vape from your CE4s, at 6v you will probably no longer have a CE4.
You aren't that experienced, that's not an attack, just an observation. There is absolutely nothing wrong with lacking experience, we were all there at some point. There IS, however, something VERY wrong with someone with a severe lack of knowledge and experience going around spreading nonsense.
Fooling around with a broken ego battery and some ce4s for two years doesn't make you an expert on every aspect of vaping, you seem to think it does. If you want to believe that, it's not my place to stop you, but when you are affecting other people then I am going to say something.
There are other people here who lack experience and instead of doing what you do, they spend their time reading and learning. When they come across your posts chock full of misinformation and outright bull, but presented with such confidence and assumed authority, they'll probably believe you, and that's not good.
You say:
"if the coil is wrapped well, it'll taste GOOD, with no wicky tastes, with no downtrodden tastes, at any voltage."
This is based on what? Your extensive experience wrapping coils and testing them at different voltages? That sentence is just completely wrong, and your potentially going to screw up other people's vaping experience by spreading stuff like this around. That's why I'm going to keep calling you on this stuff, I'm not going to allow your vaping expert fantasy to screw over other people.
A proper build will perform good at the voltage you designed the coil to vape at, period. There is no such thing as a build that tastes good at any voltage, that's a fantasy.
You say:
"I seem to prove that voltage rarely has much of a needed effect in either direction beyond 3.7V's."
Once again, more fantasy. You increase voltage things change, you decrease voltage things change. That is just a fact. A fact that every single last person here on ECF will agree with and back up.
i started with a vv ego, it didnt make any sense to me for the first two weeks, what difference did it make, i could tell minor differences from one setting to the next, then i was introduced to the beginners chart that shows you the volts ohms watts goodness... and is color coded... yay! it was great... woo hoo, it made sense and i could find a close to sweet spot for everything, but... 
