Shred is basically just really fast, technical lead guitar playing. By that definition Mick Barr of Orthrelm/Crom Tech is a shredder. In fact, shredding's all he really does! He shreds in a unique and inspired way, IMO. There are some easy ways to "fake the funk on a nasty dunk" and appear to shred while not really doing anything particularly technical and I think most of Kirk Hammett's flashy sounding solos consist of him doing just that.
SUBJECTIVE RANT
I want to point out my HATRED of the big solo in "One". I feel like that solo unintentionally changes the character of the song (as I perceive it) from something bleak into something parodistic. I also think it's entirely unnecessary and, as much as I love solos, the song would be better off without one.
He begins by playing music that I consider appropriate (but not at all necessary) for a song that's built up into something dark, sad, and morbid. Incidentally, what he plays here is a variant on a finger tapping cliche that is a particularly easy way to play a lot of notes. He continues by playing a few decent melodies and then, as he does all too often, falls into the trap of playing blues-y, cock rock guitar player cliche licks which ruin the whole character of the song for me.
Maybe licks like that would be appropriate for a hypothetical song called, "Playin' the Deaf, Dumb, Blind and Quadriplegic Blues" from a post black album Metallica release but it sounds just plain inappropriate in the song "One".