"it can be very difficult to get things done when you're waiting on input (or output) from a co-worker who's not on the same schedule as the rest of the team"

"it can be very difficult to get things done when you're waiting on input (or output) from a co-worker who's not on the same schedule as the rest of the team" That sounds to me more like a poor problem deconstruction and task distribution. For problem deconstruction though, I agree that team discussion might be desirable, thus -- availability requirement.