The value that pulltags returns is intended to be thrown away, and there is no formal definition for what it will return. I recommend not using it in an if () then. tagis[] or tagcount[] are what's intended to be used in tests.
Code:
perform field[usrChosen1].chosen.pulltags[SplLookup.?]
perform hero.findchild[BaseRace].pushtags[SplLookup.?]
Is I think what Kendall's looking for.
P.S. In Pathfinder, there are three drider races for the three spellcasting classes.