Adding a class that may or may not be flown is a bad idea. CDs are going to publicize their contests months ahead of time to fly all classes in order to maximize entries. It is not until the morning of the contest that the CD will discover that his expected entries have somewhat evaporated. If it then turns to be more efficient for the CDand allows simpler judging assignments, the CDmay drop the Expert( or any other class) and force flyers into sequences they may not be ready for. On the other hand, he may elect to fly all classes, one or more of which will have single entries. THis does happen now and more often than it should. Why make it worse.
It is much easier to adopt the split-a-class solution. No new schedules, nobody forced to fly over their head if they want to compete, easy to manage. Where's the downside? That those lobbying for a sixth class would be out of luck?
Since we probably will have an optional pre-turnaround schedule available as well, that could lead to a contest with seven classes and 15 contestants. I might turn in my CD badge at that point...
And don't forget the Nats. Logistically I don't see where or when a fifth class would fly. Getting extra days from Nats management doesn't seem to be an option unless we expand our turnout greatly. I expect the class would draw from both masters and advanced without adding much to the total entry.

On the other hand, if it happens, sign me up.
John