You realise Bulk Up Talonflame isn't made
just to beat Heatran right (because that's leaning towards what the Natural Gift sets do); Ancientpower-less Heatran just happens to be one of several of Bulk Up Talonflame's favorable matchups.
I don't wanna ramble to long about what BU Talonflame can set up on, but while there are Pokemon who completely cockblock Talonflame, there are a good number in OU that are helpless before it (Fairies, Steels, Bugs, the Grass / Ghosts, etc.), especially those who rely on residual damage to stop it (Ferrothorn and Gliscor come to mind). It is a very legitimate set that can screw up teams who look out only for CB Talonflames.
Edit: My best run with BU Talonflame; other battles consisted of forfeits from people who realised their Gliscors can't touch me :P
http://replay.pokemonshowdown.com/oubeta-72038046
I admit, I misplayed a couple of turns, but it still shows off Bulk Up Talonflame's stuff. Would you have believed your Gengar would do a measely 37% with its Shadow Ball to Talonflame? (so if you selected Thunderbolt not expecting a Roost, welp you're screwed) The best part is that Mega-Lucario cannot even hope to bring me down with Extreme Speed at the end, assuming it had it.
252+ Atk Mega Lucario Extreme Speed vs. +3 208 HP / 0 Def Talonflame: 56-66 (16 - 18.9%) -- possible 6HKO
I know Talonflame's fragility makes this set seem highly unlikely to pull off, but you'd be surprised how well its resists work for it, especially when you consider that Talonflame is totally "immune" to Sucker Punch (bar Mega-Absol), not that it would do much after some boosts anyway.