Because it proves that at the most basic level, temp control is actually working.
My post was mostly tongue in cheek.... but not totally.
I can see where TC would work great in the normal vaping range, yet still set cotton on fire if you were foolish enuff to let it get that dry.
So IMHO I just dont see the cotton burn as a valid test of what TC can do for your vape...... I see it as a "Dry Hit Protector" if you will, and that I could really careless about ! ( Since that just dont happen for me enuff to warrant higher price. )
A TC that can be dialed in with minute temp adjustment within common vaping ranges is what I expect I would want from a Temp Controlled Mod..... Thats where I could see it being worth extra coin. If it achieved this, and still caught dry cotton on fire I wouldnt shed a tear !
If all it did well is NOT set dry cotton on fire, I would view it as useless a feature as "Parental Control".
Again.... just MHO......