Ok, so you were stating your opinion - the way you wrote it, it seemed that you were stating it as fact.
That's off actual voltage/resistance readings from OEM equipment; a 3.7v battery and atomizers ranging from 2.0 to 2.3 ohms.
3.7 volts into 2.3 ohms equals 1.6087 amps
3.7 volts times 1.6087 amps equals 5.95 watts
3.7 volts into 2 ohms equals 1.85 amps.
3.7 volts times 1.85 amps equals 6.845 watts.
Ahh yes,
P = I² × R
or
P = V² / R
What should be is not always fact in electronic circuits. Until you take the actual power drain from the final destination. (Meaning amperage & voltage readings at the same time.) Albeit this is a simply circuit, things don't always react the way you think they should in a electronic circuit. And BTW are you taking these measurements under load? I'm curious as to what power readings (amperage/voltage) you get inline with the heating element. I have yet had the time/desire to take these readings myself, but maybe that will change. Again my findings were based on vapor produced and heat ranges... not that my equipment couldn't be faulty or off par.