If you take p. 105 of that book, for instance, unfortunately it's not very good. For instance, we don't know whether a single one of the songs Charles Peabody documented in 1903 even was what we'd call a blues song, as Peabody heard them. So it's unmotivated, you'd think, to go from there to suggesting that Peabody is one of the four best sources of information we have on early blues.

Howard Odum's research of 1905-1908 tells us more about blues music than Rainey's (questionable) story does. (A piece written by Rainey's brother about her suggests that she probably hadn't even really set foot in Missouri as of 1902. Abbott and Seroff have written about when she apparently really took up blues music, based on various newspaper articles they've found that described her early career as it went along, down to song titles etc.)

It's oddly misguided to just dismiss Maggio's piece, which Maggio described basing on a tune also called "I Got The Blues" by a black guitarist he heard in 1907. Read Peter Muir on Maggio and Handy's dispute with each other to see how misguided.

Merely bringing up signifying (p. 106) does not tell us how a line about a "brown-skin man" being the "cause of it all," for instance, or whatever, would supposedly be signifying something political.

P. 102: Why is there no mention of "Got No More Home Than A Dog," the 12-bar song that Handy called a "blues," indicated in his 1941 book he heard before 1900, and recorded himself, vocal and guitar, in 1938? Why does McNally assume Handy heard the Tutwiler song "in 1903"?

P. 103: "The blues would not touch the white world at all until Handy put them on paper" Wrong. E.g. Maggio 1908.

Pp. 111-112 "the weight of evidence is considerable" Nope. A lot of people saying something a lot of times because Alan Lomax said it isn't "evidence."

P. 109: Why Handy called "Memphis Blues" a blues "we cannot say." ?! Handy explained that the 12-bar stuff he used in "Memphis Blues," and onwards, was "blues music," which he'd heard folk musicians do.

P. 112: reasoning that if blues music was very popular in the Delta as of about 1914 then it's "vastly" likely that blues music originated in the Delta isn't... even reasoning. Handy recalled hearing "Got No More Home Than A Dog" in Indiana in about 1896, which is 18 years before 1914.

All in all, the usual stuff: Why write about Emmet Kennedy, who is documented singing blues before 1910, if he wasn't in the Delta? Why write about Johnnie Woods, who is documented singing blues in 1910, if we wasn't in the Delta? Why write about H. "Kid" Love, who is documented playing "Easton Blues" in 1910, if he wasn't in the Delta? Why take Maggio seriously if he wasn't in the Delta? Why write about "Got No More Home Than A Dog" if Handy wasn't in the Delta at the time? Why write about Hoffman using "Alabama Blues" in a tune subtitle in 1909 if he wasn't in the Delta? Why write about the variant of "K.C. Moan" Elbert Bowman heard blacks singing by 1905 if Bowman wasn't in the Delta? Etc.