pming
Legend
Hiya
For me, we (me and my original group) got characters to level 16 - 21 only once. In my multiple-decades of playing AD&D 1e, we typically got to around levels 7 to 10, but a handful of times (less than 5, easy) have had characters hit 12 to 14.
IME, talking to other DM's and groups of 1e/2e, I'd estimate the average "high level" character being somewhere around levels 12 to 15. The "Monty Haul" (that's what we called them back in the day...) campaigns and characters were so obvious it was laughable (re: 39th level wizards, 41st level fighters, 26/24/28 level F/MU/T...all with multiple artifacts, etc...). That's one thing I miss about 1e/2e...when you asked a player about his favorite, highest level character and he says "Thangaar, 14th level Fighter Lord", you can be pretty sure he's not a Monty Hauler; if he says "Thangaar, 33rd level Samurai Emperor of the Mortal Planes", you can be pretty sure he IS a Monty Hauler.
^_^
Paul L. Ming
I know of many groups who went all the way to 20 and beyond but I have no authority or data to say exactly what portion of the gaming community we were in and neither do you, that is why we turn to the book.
For me, we (me and my original group) got characters to level 16 - 21 only once. In my multiple-decades of playing AD&D 1e, we typically got to around levels 7 to 10, but a handful of times (less than 5, easy) have had characters hit 12 to 14.
IME, talking to other DM's and groups of 1e/2e, I'd estimate the average "high level" character being somewhere around levels 12 to 15. The "Monty Haul" (that's what we called them back in the day...) campaigns and characters were so obvious it was laughable (re: 39th level wizards, 41st level fighters, 26/24/28 level F/MU/T...all with multiple artifacts, etc...). That's one thing I miss about 1e/2e...when you asked a player about his favorite, highest level character and he says "Thangaar, 14th level Fighter Lord", you can be pretty sure he's not a Monty Hauler; if he says "Thangaar, 33rd level Samurai Emperor of the Mortal Planes", you can be pretty sure he IS a Monty Hauler.

^_^
Paul L. Ming