Absolutely ... and posture
is an important aspect too, as well as studying the mouvements of the 4 limbs to enhance consistency during playing, it's another key element.
Metronome practice will certainely improve the consistency in terms of time keeping, developping the inner clock, for sure, but you can play in time with a metronome and still be inconsistent in terms of feel and sounds, it goes beyond time keeping, you don't play a rock groove the same way you play a funk groove, or reggae, or jazz, or pop, or metal, each and every style has a certain way that is commonly expected from a drummer when he/she plays a given piece of music, this is were consistency gets a full meaning for me, to be able to play, consistently, a groove, a fill, a pattern that is suitable for the music we play, that's the point Duncan was raising I think.
Each time you sit at the kit, assuming you know the song and you're playing in time, the goal is to play
that fill, hitting the tom
that way, to produce
that sound, easy in theory, harder in reality, and it's just one fill, you'll have to play the whole song, the whole set, the whole gig, every week, and every month.
To use my mashed potatoes analogy, to get the right consistency everytime you're cooking it, it must have the right ingredients and the right amount of these ingredients, to much milk, it's runny, not enough milk, it's to thick and dry, to much butter, it's sickening, it has to have the right amount of each, the right seasoning, and it's sure to be a success.
I'll keep practicing
consistency on the drums for a long long time