Delay Units at Wayoints

The ability to delay units at a specific point along the unit's way-points is something that I would find very useful for carrying out complicated strategies without constantly watching your units. For example, if I had a unit in city A I could move it to city B, have it wait in city B for two hours, and then have it move to city C without having to log in 2 hours after the units arrived at city B to move them. If you think of any reason why this may be a bad idea, please say what it is. I personally can't think of any and I think this would be a great addition to the game.