I've been around the 'net long enough to know the value of two cents.
First, I've been reading this and other sub-forums of Apug for a few years now, but I must have missed out on the threads you mention. ( ... or I wasn't really ready for them ...) A quick search did indeed give me the threads you mention. (It should be this one: http://www.apug.org/forums/forum37/5...n-formula.html back in July -08. I must have been on a heavy work schedule back then...)
To give PE and ic-racer some kind of answer, I recon that back in 1956 the table was rather complete. (In the thread linked above DF Cardwell refers to a similar source and table from a book written in 1955. Now, I like 1956 better, as I was born then. ) Besides, while the book is comprehensive from an amateur point of view, there is also an indication of the intended audience, i.e. the amateurs of 1956. (Since when general knowledge of these matters have deterioated very rapidly.)
Anyhow, before the translated quote from the book I said that the author didn't give a lot of explanation on the subject matter. It seems like I have to 1) thorughly read the rest of the book, and 2) make my own testing...
... as I realize that both the recommended times from e.g. Ilford are "starting times" and that the compensation charts (tables or graphs) which are issued by again e.g. Ilford are recommendations.
At least I now do know where to look for more information on the matter.

Finally, this posting was more a matter of curiosity than an actual problem. I bought a Jobo a few years ago to take care of any inconsistensy problems as such.