I get that the load wood be handled better by two cells as opposed to one providing less sag but I doubt it would half it, I could be wrong. I'd say vdrop would be due to the mod sag due to the battery, both of which are increased by the build . . I run the same attys on my dual 26650 mods and I never thought " wow I can feel a difference " from the dual cells powering the same atty as my single cell mod. The longevity is there but like I'm thinking regarding sag/drop, it's not twice as much battery lifetime from two cells..
so it might be imagined like all the "my he2 hit harder than my vtc"?