I think, in agreement with the majority of 6 pages of responders, that it's kinda silly to repeatedly play a course with multiple tees (or baskets, for that matter) without trying all layouts. In particular, I don't think you really know any course until having sampled its MOST difficult layout. If you're really a rookie, then sometimes just looking off of that tee is enough to discourage you from playing. But if you play that course enough times, why not give it a shot? If anything, it will give you an appreciation for just how much better other players are.
But in the end, most of that is kind of a meaningless discussion. You can always play one layout and then play the other layout another time, or even change in the middle of a round. The tougher decision is how to decide what layout to play during a tournament. Personally, I decide between Intermediate and Advanced in all tournaments. In this region, those two divisions almost always play different layouts on the same courses, so the decision comes down to which layout I would prefer to play. So far, I have always gone with Advanced. It's because I prefer the challenge of the longer layouts, and also because I like testing myself against tougher competition.
As an aside, one of my pet peeves about reviewers is when they write a review about a course from "just the short tees," especially when the long tees have a ton more to offer and even more especially if the reviewer/player has the skills to play those long tees. Maybe I'm being harsh, but it seems straight-up lazy to skip those long tees if you're trying to give a good and fair review, unless you clearly lack the arm and accuracy to challenge the more difficult layout.