Neyland suffers, I think, because of the time factor. Many don't view football of 1938 as being "the same" as it is today, so when Michigan beats OSU 13 times out of 14 in 1901, OSu fans view it askance, it doesn't count.
It's perception and opinion anyway, your's is as or more valid than "theirs".
I think we should "celebrate" the great coaches with things other than attempted rankings, they can each be exceptional in their own right and time, without trying to compare some 1938 coach with a 2010 coach with an almost entirely different "playing field".