Yep, I'm back. As I mentioned elsewhere, I was running into frequent CTDs with v0.59, usually when trying to load a game (and once when leaving a building). Qwerty and roxor suggested the 4GB patch (I'm running under 64-bit Win 7) and disabling (via renaming) the "DistantLOD" folder in Oblivion/Data/, and one or both of these changes seemed to have mostly fixed the problem.
But when looking through some older posts, I found this from Black Shadow on 11/8/2012:
The key to the decision of problems with braking and crash Morroblivion is found out, basic part LOD works correctly including Landscape and Tree, but part LOD which incorrectly works is responsible for the DISTANT BUILDINGS!!! I think it it is connected with that that Meshes distant structures are not optimized properly and have very much plenty Polygons as a result it and leads crash games and escape on "desktop" also in the subsequent the given mistakes are saved in Save and save become unfit for use.
So my question: is it really possible that - even though my game seems much more stable at this point - the above DistantLOD "fix" has corrupted my save games so they'll eventually be unplayable? I just don't want to get 100 hours in only to find I'm, well, screwed. Thanks again all!
DistantLOD can't corrupt
DistantLOD can't corrupt saves since it is only a binary data telling Oblivion engine what meshes and where to display in distance. This information is not baked into saves.