FYI, FWIW
It turned out to be none of the above. I have an old largely forgotten (obviously) INCLUDE file that defines OWNER as a constant. Hence the use of "owner" as a cursor field name produced the fubar. You would not believe how long it took me to track this down. There ought to be some way more reliable than memory to document/flag such glitches. Thanks for the tips from all who responded.
Ray Roper