Well, when I'm doing a tiny comp (like our local club-level comps) I do it by hand, but for Nationals it is automated.
My point was that if the automated system allows something like what Katarzyna did, then it's easy enough for the registrar to look up and fix in a couple of seconds if they need to.
As far as verifying entries goes, again, it's done automatically by the system being used for Nationals, but I'm so used to looking at entries that I can do myself if I have to in about 3 seconds by looking at someone's entry. So, for a tiny comp, I have no problem doing it by hand. Really, that's another of the easy steps for a Registrar.
The tough stuff is things like getting people to pay on time, and getting people to show citizenship/travel documentation for a comp like Nationals if needed. The tough stuff is anything that at some point needs the competitor to do something or send me something. That's what I spend most of my time doing -- chasing after people for things like remembering to renew their USA Dance membership, or to submit their payment, or that sort of thing. It's amazing to me how many people will give me their email address as a contact but only read their mail once a week. I can't go an hour without checking my email, but I guess I'm just a freak.