Like Azery said there are 2 flaws in your "strategy":
1) You need Scolipede (or something similar) to make it work, if your Baton Pass Pokemon dies (for whatever reason) you're dead, Gyarados has everything he needs to kill you.
2) You said that if Gyarados is burned then he's dead and that is true but tell me how many times your Pokemon have been burned in Reborn? for me it's 2 (1 from Eclipse's Magmar and 1 from a random trainer) and it wasn't even my Gyarados.
To conclude your Clefable is a false idol, Gyarados is the true&only Beast! (yes i'm a huge Gyarados fan)