SnakeWranger, I'm sure you'll find that when you ask that question, the people most keen to answer are the ones with snakes in the larger enclosures. Many people keep their snakes in very small ones, and the snakes often don't mind at all. I had a bredli in a small (about 20x25-30cm) plastic tub until it was about 8 months and probably too big for it, but when I placed it into a 4ft enclosure (I put the old tub into the new cage with the snake in it) she stayed in there. She stayed in that little tub always, until she became too big to share the tub with the water bowl, at that point I only saw her leave it a couple of times, to drink. When she was a little over 5ft in length, she could hardly fit in the little tub and started to explore her larger enclosure. She's now about 2.5 years old and about 7ft, and lives happily in a 4ft enclosure. I don't know what she would have done if I'd dumped her in the big enclosure without the option of going back into the original one, but I figured I'd give her the choice.
I know a guy who couldn't breed his brown tree snakes (about 4.5-5ft) until he started keeping them in shoe box sized tubs (after being in tall enclosures with branches etc) possibly coincidence. A friend of mine put his 12 foot olive python in a 6 ft enclosure and it freaked out and stopped feeding until it was put back into its old one metre enclosure. Generally, if I can help it, I don't like going much less than half the length of the snake, but examples like the brown trees and olive show that each snake needs to be considered individually.
If you want to know what "is" done, see if you can visit some of the keepers with larger collections, you'll see things in some which you may not hear about first hand.
As Fuscus said, don't appologise for asking questions, the worst I'd do is not respond