Aight I didn't read it all , but as a former pro drummer (I say former cuz I stopped playing gigs in 2001) Let me add the following things
1: The drummer isn't the only time keeper so, you can throw that idea out the winder... if the drummer & bass player aren't in the pocket any click isn't going to help... the pocket is sometimes ahead or behind the actual click... sure clicks are great they serve there purpose but they're not the magic wand of great studio drumming
2: It took me about 10 years of playing drums before I realized that less is more... that buddy rich wasn't the god... that Dave Weckl wasn't the king... what I realized was that a player like steve gadd is where it's at... where he just hits the pocket (prolly why he's one of the most recorded drummers ever)
3: Not all drummers make good studio musicians... some will actually argue that Jim Kettner did a lot of the beatles recordings and not ringo... yet Ringo was great live... I really don't know the truth to this... but I can attest to the fact that I've seen really good drummer just suck in the studio (because of a variety of factors)
Anyway ... that's my two cents... now I gotta go practice my scales... cuz I still suck on bass
