I'm mainly reacting to various comments along the lines of, "Royalty need to learn that it's not all about them". Most of them know that -- and in a sense, that's the problem. Most Royals (not all) are decent at the timing of stuff that *they* planned for, but are way too soft-hearted at the zillion members of the populace who "just need five minutes of your time to do this and oh yes could we talk for another minute about that while I've got you and oh *so* sorry I really didn't mean to take up half an hour!" The unpredicted stuff tends to be where the schedule really goes to hell.
Basically, the problem is that many Royalty are fairly passive about their personal time management. Actually keeping things running on schedule requires that they be pretty strict and active about it, and sometimes requires disappointing members of the populace. And while it's easy in the abstract to say that you have to put the needs of the many first, it's a good deal harder to say no to the nice person who is right in front of you, *especially* if you actually care about people. A lot of Royals are in this game to try to help people and make their SCA experience better, and have trouble being a hardass when they really need to.
On top of this, the populace tends to be kind of passive-aggressive towards the Royals, especially WRT something like this. Everyone blames the Royalty (who are, remember, generally drowning in things to do) with not remembering to keep everybody informed about how late it's all running. But relatively few actually go up to them or their retainers and simply ask for a status update -- people mostly just sit and stew, which tends to promote blame instead of understanding.
Mostly, of course, it boils down to the usual fact that most Royals aren't managers in real life, and don't have the skills that an effective manager has to learn. Careful time management and balancing concerns happen to be particularly noticeable examples of that.
Put it all together, and I generally find that it's a good idea to "manage upwards" a little bit. When I'm meeting with the Royals, I specifically try not to waste their time. When things are looking late, I'll grab a reasonably well-informed retainer and ask if they've got a guess as to what the real schedule looks like. Try to be part of the solution, and understanding about the problem...