Having trouble with the Elite four (any pokemon game)?

I had pokemon at lvl 48-53 and i had defeated the pokemon league on diamond, so want to hear my trick? very simple it is :)... Soo stock up on about 20 revives and full restores, next you head into the elite four area, just before you fight tthe first person save the game.. so if you lose turn you console off and try to defeat him/her again so you dont lose any cash if you lose and its much easier much less presure