The human factor, in itself, is the fact that a 'groove', or whatever the hell you wish to call it, is not being late or early. It is just a human 'feel', which does not necessarily mean anything is inconsistent. Believe me, as a drummer myself, I try to do the opposite of what we are talking about here. BUT, that real feeling, of an almost perfect performance, is part of what gives the human element. Not only does a drum program not have, in itself, the ability to stray from the song in a natural way, but there is also the fact that it cannot hit a snare, a few mm's off the target. This is where it becomes the most obvious. No drum/cymbal/HH hit, will ever sound exactly the same, when hit by a real person. This is where a well responsive drum VST comes in to play. It will vary the sound, to a degree, by the changes in the velocity sent to it. It is in your hands, to vary that in any drum software. The 'Humanize' thing, can work a bit, but it is never (IME) perfect, by any means. That is the problem with software, it cant predict a feel. Perfection is what computers do. We try to randomly spread the perfection, so that it sounds like a real person. Constant HH and ride notes, will also make a programmed track sound sterile.