I'll usually do multiple takes, edit the bits in we like etc, maybe correct some parts but it depends on the drummer and I don't think its fair with any musician for me to comment here on what it took to get the performance tight.
People have been editing and dropping in for years, I spent years cutting tape up before we could edit on computers so I've always had the same approach, just easier tools.
As much as thefyn is getting on my tits, I understand what he is saying, although I feel mastadon (and his other examples) have almost a demo quality to their recordings. Thats cool tho, its just a different approach and its why some bands will use me and others will go elsewhere. I like to hear things more polished which I think is what he is hearing between the albums I'm doing as I'm not using the same drum sounds, it's just the approach.
And I'm not saying bands should use me all the time, Nevermore, Arch Enemy and Kreator for instance, we kind of get a couple of albums down the line and its time for band and producer to move on and try something else.