Doubling distillate volume with equal sized thumper?

[telefonica]

I have a converted 15.5 gal keg that I use as a boiler for my pot still. Recently, I've been considering adding another 15.5 gal keg as a thumper. Is my understanding correct that I could effectively double my output by doing so? Essentially, my stripping run would be 10 gal of wash in both my main and thumper, and my spirit run would be low wines equally split between my main and thumper? By doing so, I'd be doubling my output?

That's not how it got the name "doubler", correct? My understanding was that it got that name because it would increase (or possibly double) the ABV.

Thanks!