Col., if the mists of wonder-crowded memory allow, could you confirm or deny some speculation about the origins of the mind flayer?
In an interview with Planewalker.com, Charles Stross said that his idea for the the githyanki & githzerai, that they had been bred as slave races by the mind flayers, was inspired by Larry Niven's
World of Ptaavs. He suggested that whoever created the mind flayers (which I assume to have been your eminent self) might have been was inspired by Niven as well.
The similarities between Niven's
Thrint, or Slavers, and mind flayers are that both are powerful telepaths & mind-controllers with tentacled faces (see Wayne Barlowe's
interpretation). Knowing the depth of your reading in SF & fantasy, I imagine you might have read Niven
World of Ptaavs back in '66 or so -- especially since I've been told that, back in the day, there was so little of "the good stuff" being published that fans could & did read everything they could get their hands on. And I've seen some evidence that Niven was in the minds of early D&D folks in the form of a cool old Erol Otus booklet of creatures and magic items that featured a Slaver disintegration rifle.
Any link between this great D&D monster and the great Known Space universe would, of course, only increase my admiration for your syncretic genius.