Geez. I’ve got about 5,000 mailboxes on mine, and 2 of us split our time between that and directory maintenance. I’ll grant you it’s not the easiest system in the world to use, but a full time Exchange admin per 250 users doesn’t sound like a representative example.
Yeah, I didn’t get into that in depth so I don’t have *all the details or rationale; I’m using it as the sort of thing you see down here in the trenches with smaller organizations than what you’re used to dealing with.
You see “corner cases” like that *all* the time in the field.
FYI, the break point for “we need to have a full time domain/Exchange admin on staff” seems to be around 40-50 users. At that point, just calling in consultants on occasion won’t do it as you’re looking at almost daily issues (between the server and the users).