When I hear that (the OP's description of players) to me rather situations come to mind
where the drummer already hits one or several notes a bit out of time. That's when I
think he's losing it.
Players like Bill Stewart always show impeccable time no matter what they're pushing into,
so I don't get the feeling of on the edge of making a mistake at all.
Ok, one does come to my mind: The alienish outside fills of Virgil Donati (broken up
quintuplets and septuplets, insane layerings) often do sound like he's completely lost
it, as long as you can't follow rhythmically, but then he always nails the 1 like there is
no tomorrow, lol!
I think I do this myself but in a messy sort of way, and have always aspired to do it in a tidy sort of way. I've never wanted to be a perfect metronome or a model of precision, it's not quite as expressive as when you're exploring unknown territory.
I have mentioned this often, I am responding to this as if the tension is in a good way. I absolutely agree, safe perfect players sound bored to me, so this type of playing adds to the live excitement. Narada Michael Walden when i saw him with Jeff Beck really brought this concept home to me. He was constantly "going for it" and a few times the rhythm and the way the rest of the band responded made the feels a little uncomfortable a few times, but with a few seconds, they felt what he was doing and it all flowed back together, but it just made the performance better to me.
Billy Martin, Medeski Martin and Wood (really sloppy swampy player)
Lenny White, Return to Forever (always a little tiny bit behind or ahead of the beat when he starts embellishing and soloing within the song, but always cuts out of it clean)
Stewart Copeland (prime example is that 2 bar fill at the end of "Demolition Man" where he's whipping between the octobans and the hats while keeping the 2 and 4 on the snare...reminds me of a pilot who starts spiraling downward out of control, he's trying to gain control, juicing the engines and trying to air across the wings faster, he gives one last push of the rudders and ailerons and soars skyward like he meant it....so to speak!! raises the hair on my arms and back of my neck every time!!)
DFANIS PRIETO!!!! no doubt to the fella who said so earlier
The first time I saw Jim Keltner play,it looked like he had been playing 3 months to me,it looked like he was going to screw up every time he played a fill and sometimes while he was keeping the beat,but his fills always turned out fantastic,I was fascinated.
Jimmy Page plays that way,he sounds like he is getting lost in the middle of a phrase,but it always turns out well.
I read an interview with Frank Beard of ZZ Topp,and he called it playing in a" fall down style",he likened it to a person descending a staircase then loosing their balance and falling down the stairs but righting themselves again on the last 3 steps.
I think I found a perfect example of this quality, Mark Guiliana's playing in Avishai Cohen's The Ever Evolving Etude. Check out the drum solo at 4:40, you can actually hear his sticks clicking when he gets really into it.