Darkangel,
and shredding is just scales, right. And when Yiggie finger taps all those alternating notes with the fingers on his right hand, it counts as just using one pick since he is still holding it.
Don't underestimate these guys and explain away what they are doing.
Yes banjo players roll--picking with their thumb and two fingers, a style invinted by Earl Scruggs in the '40's, but the roll's pattern changes many times in a song and NO they are not just holding the same chord position on different places of the neck. Heavy metal power chords don't work on banjos. They are more complicated than that.
Ever seen a concert violinist play? The next time you do, watch their left hand and fingering. Thats what guitar and mandolin flatpickers and banjo players do.
If you didn't like the samples, that's fine. Just don't insult their playing and talant with some lame passive aggressive remark.
If rolling is so much easier, let hear you give it a try.