Is it now a no-brainer to TM a Bite/Crunch Gyarados to Waterfall/Hydro Pump?

Gyarados with B/C will deal more damage than a Tyranitar with the same moveset if you don't bother dodging Focus Blast. If you do then it doesn't really have a use because a Tyranitar will do more DPS and total damage output if it doesn't get one-shot by Focus Blast.

If you're often in raids where a W/H Gyarados would be the best counter but you're having to use suboptimal Pokemon because you don't have enough of them, then sure, TM it.

It is now a significant distance ahead of vaporeon for water dps. Likewise, sims show gyarados as well behind others in Psychic counter roles. Crunch is not a great attack to begin with and gyarados lacks STAB. Sure, it can fill a niche role of a lazy counter for FB mewtwo or 'Zam but if you can dodge even one charge, pretty much any other counter is more reliable. even DT/O Dnite sim ahead of Gyardos with neutral dps if that tells you anything.

I never really understood the Bite Crunch Gyarados hype, it is not even a top 5 Focus blast Mewtwo counter and B/HP is just as good at level35+.

Plus, the odds of getting a FB Mewtwo is pretty low while the best water mon in the game will always be useful.

it is said that gyarados will get dark typing with his megaevolution.
i guess that's why people including me keep a double dark gary.
but i play since the second week the game was out and have more than one already tm'd to waterfall.

Its all depend on where the trainer llive at..
For me i have a good amount of magikarp spawn if i am willing to go around 2-3 km from my home
So yeah for me it is a no brainer
Already TM 4 WF/HP gyara with high level and good IV
Keep 2 with B/C, and 2 with legacy dragon moves

But with trainer that dont have a lot magikarp spawning it can be problematic, especially if they value the legacy moveset

My Gyarados has Bite and Crunch and I am just going to keep it that way in case I ever get an ex raid pass. After all, other than Houndoom, Mewtwo counters are hard to find.

I would, if I had charge TMs. Unfortunately I used them all on Ttars.

If it's your best Gary, yes. If you've got other candidates, and your Bite/Crunch version is lower on the pole, you might want to save it (because why not?).

I think keeping a Dark Gyarados counter just for Focus Blast Mewtwo is GREATLY overrated. The odds of having to do a shorthanded FB Mewtwo raid are so small so as not to warrant keeping yourself from obtaining the best Water attacker in the game. And a Dark Gary lands at around sixth on FB counter lists anyway. It's just not worth it. I did keep one B/C Gary, but that's because I had three higher-level Water versions to convert.

TM away.