How do you do an innovative design if you don't conceptualize it first?
Mangini has an idea of how he wants to orchestrate the drums. He plays open-handed. Then he wants to shift from light to dark-sounding cymbals to mark changes in keys (usually shifting stanza, then chorus). He also wants to match runs up and down the scale of the other melodic instrument one tom per note, which you can not do in the traditional setup of toms arranged clockwise because the arms would cross. So to be able to hit one tom per note, the toms go down the scale and are arranged RLRLRLRL. Are there kits with these features that he can play on before he designed his own kit? No.
Stupid? God forbid somebody designs a new kit based on how he imagined he would like his drum playing to sound like.