Correct. Unless you're doing a precise transliteration "oo" and "ou" aren't normally used except for data processing, "oo" for おお in passports and "oo" and "ou" in words and place names (e.g. Hiroo, Toyoura) where the sounds are in separate words (i.e. characters). Legally for Tokyo I think "o" "ō" or "ô" are all recognized but I'm not really sure. Glad to see you're as sharp as ever.