Fine so keep them in rush hours and have it unmanned during off-peak periods...I don't think every single train from ~5am to ~1am needs a person on board. Automated should be put to full use. I think even if some times delays happen for stupid reasons, i think overall the benefits outweigh the negatives.
I do agree though that if they are put to use as POP checkers throughout the train ride, that would then be a good use of having someone on board...They would basically be doing two jobs...Fare Collector & Train Operator!
Toronto has to Severely change its employment model for transit because the current system is ass-backwards and a huge drain on revenues...more POP and automated fare gates is the way to go. Start by eliminating fare collectors from low volume stations like Bessarion in off-peak periods and putting in fare barriers. Presto will surely help with this process more...using a phased approach, soon the entire TTC can have unmanned stations across the network.
Let the TTC focus its employer resources on real needs like driving buses or maintenance instead of having overpriced fare watchers...