If I see a instruction to press "CTRL +" (meaning Control-PLUS), I don't take that to mean the + key on the numeric keypad. Maybe I am just being picky, but keys on the numeric keypad often carry variant semantics from those on the main querty section.

Further, the effect in Opera is not one of "increase font size", but one of "change screen magnification". Again, these are semantically distinct operations.

Now if the anonymous respondent meant the numeric keypad in his/her wise-ass response, they failed to make that clear, leaving plenty of room for me to make the interpretation I'm sticking with... :)

yours,
Michael