Jeff Beck may have great tone but he doesn't play metal and he doesn't have the tone for metal. That doesn't mean he can't but he doesn't play in that genre and hence that's not his tone so I don't think he's the best choice to argue the point.
Vic there's no way in HE double hockey sticks you can play metal with your middle finger you might play alot of music that way but you ain't going to play metal like that. Using your fingers would give you a complete different tone even if you handle the extremely fast accurate picking required since the flesh in your fingers gives some give compared to a hard pick but even if you used your middle fingernail I doubt you'd be able to ever get those fast syncopated rhythms using it.
For the most part there isn't much finger picking in metal since alot of it's about fast, loud, aggressive music that has little melodic structure. Some of the genre's do have alittle more melodic lines in them and there may be some guitar parts that might be fingerpicked but the metal I'm talking about like early Metallica, Slayer Pantera and a million other metal bands I don't think can be played without a pick.
If you look around enough you'll see advertisements for picks made especially for metal. Like Ande mentioned pick type is very important for metal players. I don't think that go to great lenghts to market picks to a certain type of player if there wasn't some importance to it.



