It's all because modern kids want 5 bassdrum mics, or else they don't buy the record and they get angry with their parents and start to trow with skateboards and refuse to eat their happy meals. Or they even kill themselves and leave a note with "**** korn" on it.
I think that Fillipeti guy (never heard of him) is a good man for doing that.
Now get 5 five microphones and make sure everyone of them is out of phase and you got that killer korn bassdrum sound to die for too.