I think the end result of this will be similar to what is going on a Kennedy now due to the closed runway. I bet airlines will push for taxi slot times and to delay boarding until they are sure departure can happen within say 2 hours at most. It will still result in cancellations when jets stack up at the gates, but if pax haven't boarded yet, the clock hasn't started.
Whole new sets of problems and by the wayside goes on time stats! The new black eye.
YMMV...Philly