I know Kirk Hammett took lessons from Joe Satriani, but when did he take them? It's a question I've always thought about and never really could find an answer. Was it before he joined Metallica? During his time in Metallica? When?
I think they took a long break after Master because of Cliff dying and hireing Jason, so he would have loadsa time for lessons.
According to Wikipedia, it was before they began recording Kill 'Em All, but then again it's Wikipedia.
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It wasn't before Kill Em All anyway. Its more likely to be after MoP