There is no excuse for playing metal on a Strat or Tele with a stock output Tele or Strat pickup . If you do, then may God have mercy on your soul. There are so many great dedicated drop in replacement metal pickups that can go into a stock Strat or Tele ( the best of which are Duncan and Dimarzios-but you can find cheap adequate high output pickups ) IMHO, you must be mad or broke to play metal on a stock Tele or Strat with a stock output Fender pickup.
That said, I don't bring a 16 inch chainsaw to cut down a redwood tree. If I want Metal, I'm bringing a dedicated metal guitar with dedciated metal Humbuckers.I'm talkign modern metal. Not that you have to ..use what you got, but I don't bring a knife to a gunfight.