Thanks as always, Kyle.
Two different IF functions exist for MySQL. See here:
dev.mysql.com/doc/refman/5.5/en/if.html
- the blue "Note" box early on underlines the fact. Or google "mysql if then" and get a lot more on this other function.
However, I am familiar with the one you're referring to, had also tried it (did work in a very simple format), but when there were nested conditions, other than it getting hard to read it then failed in the same fashion... and I had paid really careful attention to getting the syntax right.
Anyway, we agree it works perfectly fine with CASE, no problem, and that's what matters.
Thanks and cheers!