hello again!
after discussion we discovered quite big lack of this model: maintenance. the config file could easily exceed any reasonable size, and that is something we probably don't want (wine-users: send your config file...).
so here is the revision: application specific config information could be stored in separate directory (let's say ~/.wine/app-config), one configuration per file. each file will contain an entry which determines its validity, e.g. "Filename" = "homesite*.exe". then there will be the [DllOverrides] section and maybe some others.
this breaks wine configuration into two pieces: application independent part (stored in ~/.wine/config, contains drives, paths and all other independent stuff) and application dependent part (stored in ~/.wine/app-config, contains things like [DllOverrides]).
on startup wine will load ~/.wine/config and pass through files stored in ~/.wine/app-config directory. the first match against regular expression defined in these files (Filename=...) causes to overwrite some sections from ~/.wine/config.
the advantage is much easier maintenance. the disadvantage could be that you can't see the whole configuration in ~/.wine/config file anymore - some settings could be overwritten by optional file in ~/.wine/app-config.
what do you think? martin