I was thinking about how some books have the Enterprise crew going back to Earth for shore leave during the five-year mission, and this kinda bothers me, because I've always thought of the whole thing of the 5YM being that they're "out there" far enough out that it would take them months to get back to Earth, so they can't just go back for a little break whenever they want. The discussion is then about the nature of the "Five Year Mission." Based on only the onscreen evidence and not the books, do you think that the 5YM was a specific mission To Boldly Go, for five years without periodically returning to Earth, but only using outlying bases for rest and resupply, or do you think that the 5YM was really just that Kirk was assigned to be captain of the Enterprise for five years, with no specific tasks attached to that assignment? Or anything else in the middle. I know this has been discussed before, but basically, it's just all about what exactly the 5YM was (if it was anything at all).