Chasing Cordy
Potential
I believe by season five's checkpoint speech, Quinten and the other watchers knew about Faith.
Seeing how they were so intent on being rigid with rules, why would they even ask Buffy to continue? She wasn't the real slayer at the time.
Seeing how they were so intent on being rigid with rules, why would they even ask Buffy to continue? She wasn't the real slayer at the time.