That guitarist might not be a bass player, but most likely has played with thousands of them and most of them were most likely amazing.
"Thousands of amazing bass players." lol
Keeping it real now, I've played with a couple dozen "amazing" horn players, but I'm not a horn player and still don't know enough about those instruments to give good advice. I could puff up and pretend that my "experience" working with all these horn players makes me qualified, but I'm not.
And if I did give advice about horn playing, and then actual horn players with many years of hands-on experience disagreed and explained why my advice was bad, then I would be exposed.
Or go through life gullible and easily influenced. Your choice.
Re-posting for the profundity of it:
Just my opinion: if a guitarist -- any guitarist -- offered me advice on my bass playing that involved palm muting and using all downstrokes with my pick, I'd probably follow up with some conversations with actual bassists, because it kind of sounds like he gave you advice on how to play bass like a guitarist would.
Maybe I'm a bit jaded by reality, because over the years I have heard some of the dumbest stuff come out of the mouths of "experienced' and "talented" guitar players regarding how to play bass, and more than once I have handed my bass to a "talented" guitarist just to witness some of the most shockingly god-awful un-musical bass playing conceivable.
OP may think this particular world-class guitarist is a good player, but that doesn't stop his advice from being questionable, as several posters to this thread have attested.
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