there are situations where it's not as simple as "sharing an optimization."
You're right, of course. But I don't believe those situations are relevant to data files, because data files only contain information, not logic. I would suggest that in the case where editing the data file both is and is not an optimization (due to differing perspectives), it's something that should be addressed in the parent script's handling of the information, not the information itself. Thus I feel pretty confident saying that it's beneficial to share
any data file edit you find personally useful.
Take this Candyblast issue: BatBrain is concerned with correct information, and I believe people knew that and thus did not share their hack (which LIES!), on principle. People did, however, alter their personal copies to achieve correct function. BatBrain's inability to function correctly given correct information thus caused one of the situations you're talking about -- a conflict between correct information and correct function. The problem was with BatBrain's use of the information, however, and sharing the hack would have at least led to correct functionality for all users until the fix was implemented. I don't blame anyone for not submitting that hack -- as I said I believe it was withheld for very good reasons -- but in future I encourage everyone to view data files on the Map Manager as a sort of Wiki, where any one person's edit likely reflects the views of several and is thus helpful. In the event that it causes problems for others, they may feel free to edit the file as well, or report the problem so that the script author can account for multiple perspectives. These edits are not permanent.
Back on topic: How about a
single SVN repository for all data files, which allows anonymous read/write access, containing a subproject for each data file? The Map Manager could then be reprogrammed to use that repository rather than its own data storage. All the benefits in one package?
ETA: @Bale: I missed whatever "defacing" you did to batfactors. That said, since I view it as a Wiki which people are likely to fix if it's harmfully wrong, I don't mind, either. It's constantly in flux as information is added, spaded, fixed, or refined; mostly by me but often by others (especially new skills). I should let you know, however, that instead of commenting the chefstaves out, you could have given them the "custom" keyword to remove them from consideration without actually removing them from the data file.