It could be said that simply throwing strikes is good control.
But commanding the strike zone is all together different and even includes the ability to throw good non strikes. This is a combination of good stuff and the ability to locate.
Often good mechanics is confusing. There are general guidelines, but not many pitchers have exactly the same mechanics. The perfect mechanics for one pitcher may nopt be perfect for another pitcher. The best pitching coaches use mechanical guidelines but incorporate them with a pitchers "natural" ability. These days I think we see too many using the old cookie cutter approach to pitching and hitting. That might work for some, even most, but definitely not for everyone.
That said I do believe good mechanics can help a pitcher improve both velocity and accuracy. Good command to me is a result of mechanics, feel, confidence, stuff on any given day. Not very many pitchers have their best command nearly everytime out. In that repect I suppose it is like shooting a basketball in some way... Even the best shooters have some off days.