True, it's anybody's guess what the situation was, without hearing the session files. I'm pretty regularly dealing with students whose time needs improvement. If you're not reliably hitting beats 2, 3, and 4, you're probably not hitting "1" very often. It's usually the "1" that is most problematic, because of fills or transitions.That's why I explained my assumption. If the OP is nowhere near hitting the whole notes - then the studio guy has a point and the OP does need to spend more time with a metronome. If the the OP is hitting the "1" of every bar reasonably well, that should be "close enough for Rock 'n Roll", so to speak.
My point here is that timing accuracy should be developed, along with, and in addition to, groove. If a drummer sounds mechanical (and I know some players like this), it's their fault, not the metronome's. A metronome does not stop Steve Gadd or Steve Jordan from having their feel.It's a good exercise, yes. I could use more of that. But if it becomes the way a drummer plays, all the time, imitating a drum machine, it's not a great sound. A drum machine could do a better job.
Taste does matter here, but I think most of us are on the same page. When I think groove, I think relaxed, slightly swinging 16ths, or a shuffle played that exists between triplets and dotted 8ths -- quantifiable things.But mostly it's a matter of taste. There are people who think Stewart Copeland's drumming "improved" after the first two Police albums. The first time I heard someone say that, I thought they were joking.
SC is an odd bird. He sounds like a victim of adrenaline -- rushing ahead and squeezing notes too close together. His real strength is writing unusual parts that work well.