You have provided no academically acceptable evidence that the 1860 census shows 30.8% of white households in the seceding states were also slaveholding households.
Simply saying it over and over is not a provision of evidence.
Take for example, actual words of DeBow, "Assuming the published returns, however, to be correct, it will appear that one-half of the population of South Carolina, Mississippi, and Louisiana, excluding the cites, are slaveholders...."
If you assume published returns to be correct, and if you exclude cities, you manufacture a desired statistic.
However, this is hardly an academically-accepted methodology.
Debow in 1861: "When in charge of the national census office, several years since, I found that it had been stated by an abolition senator from his seat, that the number of slaveholders at the South did not exceed 150,000."
So DeBow is talking about the 1850 census, which was not as detailed, forcing DeBow to his calculated estimate. Whether that estimate is accurate, however, is irrelevant if we're only counting the actual enumeration and considering it academically acceptable, as you've said. DeBow's 1854 report on the 1850 census cited a number of shortcomings in the methodology of counting slaves and slaveowners, and his suggestions were incorporated into the 1860 census. That census yields much more detail, including the number of free white households and slaveholders. While you can search the database I linked to above, here's the relevant results on a nice table:
http://alpha.furman.edu/~benson/docs/shfam60.htm
The total number of free families we get in the seceding states is 1,027,967. The number of slaveholders is 316.632. That gives us 30.8 of white households owned slaves. Yes, there's still an amount of estimation there, but here's the footnote from the bottom of the link above (from an academic):
"Note: These numbers should be considered a close approximation only of the percentage of free households that held slaves. While the normal case was that only one individual per household held title to all slaves, under special circumstances census takers sometimes counted more than one individual from a family as a separate slaveholder. On other occasions the census taker excluded out-of-state slaveholdings. Because slaves were taxed and census marshalls were government officials it is likely that under-reporting of the numbers of both slaves and slaveholders was higher than under-reporting of free families. On balance, therefore, these error sources should cancel out."
what he IS good at is parroting (ad nauseum) the drivel & bilge promulgated by the most extreme, leftist, REVISIONIST, south-HATING, poison-ivy league academic elitists. (most of the same damnyankee apologists also hate the USA, btw. i wonder if he knows that???)
free dixie,sw