Thickness of the wire is just a crutch, to keep resistance in acceptable dimensions.
Surface area is much more important for vapor production, so 28ga*3 is much more efficient than a single 22ga for example, because there's much more coilsurface in contact with the saturated cotton, although the resistance is about the same.
To me it's a balancing game between surface area and ramp up time.
I use dual coils, have used but not made some twisted fused claptons and a couple different fancy coils.
My go to is mixed twisted coils. I've had great satisfaction with dual coils made with 26g, 28g, and a flat .8x1 (I think) kanthal wire twisted pretty tight. 7 wraps 2.5 baby. 75 to 100 watts mmmm so much tasty warm vapor!
I've twisted up some monsters... All kinds of variations of different wire, nichrome mixed with kanthal is pretty if you dry fire it at very low wattage...
I did a single coil in a velocity clone once that was 3 24g wires, 8 wraps around 3 mm I think, but it had horrible ramp up and was a hot vape and stayed hot. Still have the coild because it colored in an interesting way even though it was just kanthal a1.
I have no idea what you'd call them but for a while I was twisting 2 wires together and then twisting that first twisted wire in the opposite direction, which is extremely interesting, makes a chain with open loops along it. Yes I've made dual coils for and rda out of that stuff. Not the best vape, but I encourage others to try this out if they haven't because it's fun

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Who else loves twisted wire ??