Pokemon Page: Defensive Smeargle

I'm gonna preface this by saying I know full well Smeargle is a gimmick Pokemon and not a viable attacker or defender by any means beyond style points. That said, I feel this is worth asking about considering a little blurb was written about it:

"Confusion + Dazzling Gleam would give the best defensive coverage from fighting types. Alternatively, just photobomb a Blissey for Zen Headbutt + Dazzling Gleam, not that Smeargle is a passable defender at all."

The way the text is worded implies one would need to TM to have this move combo like you would for Fury Cutter/Hydro Cannon. What's to stop someone from just photobombing their Gardevoir than can already learn both of these moves? Surely it's worth mentioning over the Blissey workaround.