taunt is for breaking walls and preventing status, ie toxic from chansey as well as for deo-s etc. The tankiness is really useful in taking thunders and icebeams etc and not get 2hkoed.
Computer back up!
The end of gyara...
Trickroom: yeah Gyarados isn't that great in Ubers. Try Jellicent maybe, since it worked out great for me. Gyarados kinda lacks recovery and bad stats which is horrible.