1) No longer available.
. . . it took too much CM time to answer phones, email and arrange
. . . it took diver time, and they have other water-tank duties
. . . there were too many complaints when people couldn't get it
. . . there were too many complaints if it didn't come off as planned
2) This is a case of too many people knowing about it and spreading the word.
3) Sort of like killing the golden goose.
NOTE: It was supposed to be ended in January 2008, but with little notice there were too many complaints it was being stopped. So, WDW put a "spin" on it and said it was for the second YOMD. Now they had a reasonable excuse for halting it.