If IGFA (International Game Fish Assoc) rules interest you:
"
The lure must be a recognized type of artificial fly, which
includes streamer, bucktail, tube fly, wet fly, dry fly, nymph, popper
and bug. The use of any other type of lure or natural or preserved bait,
either singularly or attached to the fly, is expressly prohibited. Only a
single fly is allowed. Dropper flies are prohibited. The fact that a lure
can be cast with a fly rod is not evidence in itself that it fits the
definition of a fly. The use of any lure designed to entangle or
foul-hook a fish is prohibited. No scent, either natural or artificial is
allowed on flies. The use of scented material in a fly is prohibited."
So no, it's not a fly for a world record. Is it fly fishing to me. It you can present it with a fly rod and it makes you happy and your aren't trying for a world record and it's LEGAL. What the hey, go for it man. It's just a game, no one came down from the mountain with a stone tablet on this stuff. Some people would like it that way as long as THEIR way is the way written in stone.