The practice of keeping characters played from 1st for "one-offs" was de-rigor within my circle of friends and still continues to this day. However there have been some substantial changes to how successful this is.
Our situation, was, like others where this was behaviour appears to be common - University. With such a large group of DMs and players to choose from we were able to mix and match and play in each others adventures. DMs had worlds and in those worlds events that effected players occurred. Players would have what was referred to as a home world where their castle/tower was based but they travelled to other places and did other adventures. Even the same adventure. I'm not sure how many times the giants series has been done.
A DM would start with a given group. Get so far and stop running, but another would leap into the fold. Taking off where they left off for a couple more adventures.
We'd each have our adventures of reknown, where one group of characters had done this thing and another group had had that idea.
Pre-gens were, and still are in my opinion, the weak link. Particularly as one got to higher levels of play (12th-17th) the pre-gen was the weak point. Not because of the player nor the character but because the player did not know the character. More often that not the Pre-gen in a given game died, worse still was when they caused the death of a proper character, one that had years of personal investment. So while on occassion they were allowed, most of the time they were a liability.
Of course there we're occasions of the dubious character and supra-power items however we had conveinient Planar-Customs that would 'hold' any gear deamed too unbalacing for a given world. Often was the phrase "but my DM from home let me..." hailed. Normally on the most outrageous of items. One item we were all careful to look for was the "pencil of item creation" where any item the character required would appear on the character sheet the next time they adventured.
Every convention in the 90's that I went to I was able to offer up an adventure (normally 10th+) and would get a good response from players from all over the country. Some of the most interesting games I'd had have been with these new (to me) players, playing characters they know intimitely and playing with aplomb.
Over the course of the decade however the number of interested players became less and less until about 2000 I had a core goup that I'd seen pretty much ever year there. No new players were coming forward. Of course this is during the rise of the card game.
My last year of running 1ed/2ed one-offs at conventions was 2000. The birth of 3ed. That year I travelled to the US GenCon and managed to find a full group (9 players) of high level characters and had a very enjoyable time. However since then, apart from a 2ed campaign that took another year to finish, I've not run another 2ed thing.
We've all tried to do the same thing with 3ed. Unfortunately we do not meet very often anymore (once a quarter) and our numbers, have gradually depleted to just eight of us. We even specifically set ourselves up a round robin group, where each of us would take turns DMing this new-fangled 3ed. We managed to get our group, over the course of three years, to te giddy heights of 14th and we are still playing 3ed. However 3.5ed is now here with all its improvements and modifications and while we're unwilling to convert just yet we also realise we're being left behind rules-wise.
On of the major causes of the end of one-offs has been 3ed. Maybe because of the proliferaction of personal prestiege classes, huundreds of official/semi-official ones, that finding an adventure to challenge all has become the challenge. Maybe its something else. Whatever it is people do not seem to have the store of characters that they are will to play in other games.
I recently returned to the university games convention to run a one-off that was basically an adventure I'd written for the round robin crew and found that no one had characters higher than 10th. The reason - no one ran one-offs and only played in campaigns. Those campaigns seemed to all finished after an academic year and during that time they'd only gotten to 9th/10th. In the end a couple of old-timers converted their 1ed/2ed characters in order to play.
I still hate pre-gens.
