Tempo is a really big deal for me, because it directly affects the feel.
Yeah....I forgot that part. What if you played the tune backwards 5 times slow, then one time fast before returning to the tune in forward progression at a medium slow tempo then half fast tempo while morphing from the key of A to E flat? Now that's an exercise in musical science.Science! That's what!
Establishing the tempo is important. Everyone starting at the same tempo is just as important. Meter depends on what you're playing and who you're playing for.
Key is pretty much a dealbreaker. Doesn't matter how good your tempo is, if your bandmates aren't in the same key, chances are the song's already shot.
In my opinion the tempo of each song a group plays should be written right on the set list and everyone in the group should be as committed to the tempo as they are the key.
Last year, I was listening to gig recordings and appalled at how fast some songs were. Even considering that some bands bump up the BPMs for some songs in live settings. And for others, live matches the album temp. So last year I wrote down the BPMs of each song in my tempo app and count them off at the agreed upon tempo. The feedback from the band mates has been incredibly positive and and set me apart from their previous drummer. Our lead singers usually thank me at every gig for how much better it now feels to sing and not rush. My only regret is I did not do this years ago.
Actually, I will sometimes hear the song play in my head, no mouthing the words or moving my hands or tapping my feet... just hearing it playback as if it's on the radio. Then I've got the tempo, and if I know the song well enough, it plays back in the correct key as well. Just takes a few seconds, and depending on the song and where the hook is, I may 'hear' the verse, or the chorus.
As for song tempos in general, I find there's a range in which each song feels and sounds its best. Most songs just don't work if they're too fast or too slow, and it has nothing to do with the players' ability to play at the different speeds. It's a feel thing for the people listening, and to an extent, the players. In other words, the players know when something doesn't feel right, even if it's being played perfectly. Some songs have a wider range of workable tempos, other feel weird if they're just 10bpm to fast or slow. For example, would Sex Machine sound/feel as good if it was much faster or slower? That's one that has a narrow range, and to not know the limits of that range when counting it off is just poor musicianship. Or maybe it's laziness. Or maybe it's rationalizing that tempos aren't that important.
Tempos are in fact very important.
A lot of the time they're doing that because they have dancers, video or audio synced. I've personally seen instances where sticking to a click made things sound a little draggy or less energetic too.
..For example, would Sex Machine sound/feel as good if it was much faster or slower? That's one that has a narrow range, and to not know the limits of that range when counting it off is just poor musicianship..