You're right. You should distrust any argument Norquist makes about taxation - you'll find that they are either wrong (as in this case) or strawmen. His actual goal is to defund government and you should assume anything he does is done to further that goal. And lest you think this is just ad hominem ranting, google "drown government in a bathtub" and look at the effects Prop 13 have had on California municipalities.