Scrivener of Doom
Adventurer
Lets not kid ourselves here.
Besides stat blocks for NPCs and monsters and the occasional special race/spell, the BULK of the material generally goes unchanged from edition to edition in settings. Usually its just re-writes for consistency or editorial, or continuity.
When I was putting together a series of blog posts to expand Lost Mine of Phandelver by expanding the notes on each location on the regional map, I went back through all the source books that covered those locations. I was amazed at how many of those locations really used the same descriptions across three or more editions!
