Earlier quoted context omitted.
Poor blacks, unlike poor whites, are subject to mass incarceration. Edit: this is technically incorrect, see dragonwriter below.
Poor whites and poor blacks are both subject to mass incarceration; though poor blacks are incarcerated at even higher rates. This is clearly among the factors that, on average, favors poor whites over poor blacks. I certainly did not deny the existence of such factors (I even enumerated some of them.)
Yes, good to point that out.
My argument (implicitly) was that this is a really huge factor which gives poor whites a "net advantage."