"On Scheduled Tick"

It's possible to "schedule a tick" for another block.

It's possible for a block to be triggered by a random tick event.

It *doesn't* seem possible for a block or procedure to be triggered by a scheduled tick (and no, if a block triggers on random tick, it doesn't also seem to trigger on a scheduled one).

If it were: 

This would allow delays (a relatively common request).

It would allow specific operations to occur only when a tick is scheduled to do so.  And it would allow multi-block machines, where "this block schedules ticks for that block when these conditions are met, which in turn...."