Install ChatSetAttr and run this command while selecting an PC token. It will turn off most messages, except for spells that have higher level casting. This is one of those cases where the difference between setting something programmatically, and doing it manually makes a difference. Basically, this writes "innate" into every "innate" field of every spell. If you do this manually, it will work across the board. If you use the script/macro, it will have the limitations I describe.