Did my skull just go in a vice or what?

Really, what's the point of coming up with a photo call list for a show with costume changes? No matter how I try to plan it, someone will change faster/slower/ridiculously slower than I plan, and we'll have to revamp the order. Why do I bother?

(Because I'm a stage manager, and we like to inflict pain and efficiency. Could this headache go away so I could decide what should be first, McSmogg or the Swamp?)