OK - sorry for the interruption - turns out this was a mySQL
issue, rather than a DW one.
For some reason, even though I dropped the schema, and
dropped the user, if I recreate the user it would not pick up the
new permissions I assign to it. Why it would work remotely through
DW, and locally through phpMyAdmin, but not from a web page is
still a mystery to me, but I was able to resolve it by creating a
brand new user with a unique name, and assigning it the same
priviledges that I _thought_ I was assigning the other user.
hmmm... but I get to move on with my life, at least.
Dean