It's probably not exactly the same vape using a dual coil in a tank, but I just walked over and vape the DCT DC tank on the eGo and it has a warm vape. It's not a hot vape, but it's not a cold vape either. It's noticeably warmer than 4.0v on a 3 ohm, which I'm currently vaping on my Provari, which is about 5.3 watts. At that level, I get about the same exhale quantity as I did with a cigarette. If you do that calculations on a 3.2 ohm coil and double it, you get 7.3 watts, which is a pretty good vape level.
5.3 watts is pretty cool. I guess a dual coil could be warmer than the resistance would indicate, since it is somewhat additive. You are pre-heating the second coil with the first one, but the additional heat doesn't make up for the additional current draw. I'm not sure what you mean by doubling the 3.2ohm calculation to get 7.3 watts though. You're not doubling the watts in a dual coil.
In you grill analogy, the two burners side by side are additive in one spot that is concentrated on the steak. True the temperature of two cooler bulbs would be less than the temperature of one large bulb. I guess the choice is in the vaper's mind. I consider the dual coil to be a warm vape at 3.4v and a really warm vape at 3.7v. I wouldn't want it any warmer. We have people who report vaping 2 ohm cartos at 6v. That would be terrible and possibly damaging to the hardware and to the lungs to me. I'd be wondering how much acrolein I was ingesting.
In my grill analogy, I wasn't assuming the burners were side by side. One was in the front yard and one was in the backyard. A more correct analogy would be in a two level range where the lower burner and higher burner had nothing separating them. The upper burner would be somewhat hotter than the lower one at the same energy draw. Again, the difference wouldn't be enough to compensate for the fact that you're burning more energy per calories of heat produced.
2ohms at 6V is 18watts and that's ridiculous. Most people prefer 6-10W and a "sweet spot" around 7-8W. There are always hotheads who claim to regularly vape at 14W or more, but I suspect there's some braggadocio going on with most of them. Either that or they are mathematically challenged.
Lots of vapors talk about how variable voltage ecigs should manage and regulate watts, not voltage. I think they have a point.
I agree absolutely. Regulating voltage is a crude method to regulate watts, which is the ultimate goal in the first place. It's like regulating the time it takes to fill your sink by adjusting the drain stopper. Or regulating your car's speed by dragging the brakes. There is a Russian made PV with one of those crazy Russian names I can never remember, Smovetra or something like that. It looks like an industrial, heavy duty Provari but it has variable voltage AND variable wattage up to 14W, IIRC. Also rebuildable atomizer/tank systems. There must be 100 different options and I never could make heads nor tails out of what part did what, even though the page was in English. If I could ever figure out what it is I wanted, I'd love to get my hands on it.