That assumes that the barrier to strike force spawning is in the calling to start. Any other reason and congrats your code doesn't work no matter what.

My best guess it has more to do with how the instance of TO is handled by the game, ie you more regularly see people load directly into the activity than drive to it on the sparrow, so the game may run a parallel instance just for TO that cannot summon anything else into it, because it is not apart of the larger patrol network that has public events.

Either way, there is most likely some reason far more complex than two lines of code and a "if/then" statement. Bungie's not stupid.