Hi Eric, when I found this out last year, I communicated with Jim about it. I hit upon this by accident. At the time, I had made a rather significant re-organization and as a result, there were momentarily a lot of files in the trash. I then synced and immediately noticed that things were funny. Whatever I did, some files would sync, others didn’t. I decided to look at the actual files inside the DB package. I was suspecting that maybe some odd permission issue would prevent some sync operations. Then I noted something odd. One file that would never sync properly was one of two files inside that particular folder. But I realized that the other file was one that I recognized as having put in the trash on that day. I was surprised that it was still there. I realized that “putting in the trash” probably doesn’t move the file, but only adds a flag. It suddenly occurred to me that the existence of this file might have something to do with my problems, and I got rid of it by emptying the trash. Lo and behold, things worked perfectly! My hypothesis is that if one of the DB subfolders contains a trash item, the other, non-trashed items in the folder will have trouble syncing (note: I say “hypothesis”, because I did not investigate this further; all I know is that once I started keeping the trash empty for syncing, I never had a single problem again).
In the past, in some forum discussions about issues with trash, official advice was “do not keep anything in the trash”. I think that is a little misleading. I agree that people should not use the trash as “secondary storage”, like a garage full with decades of junk. But keeping it strictly empty at all times makes absolutely no sense. In that case I could as well use the equivalent of the “rm” command. The trash is there to put things in that (a) are definitely slated for deletion, but (b) linger for a couple of days, just for safety. For example, in Mail, I chose to finally delete trashed files after 30 days. That makes me very comfortable to delete things, because if I realize that I deleted the wrong item after a few minutes, hours, days, I’m still good to recover the item.
So I’m not keen on having to kill my DT trash just to sync, but on the other hand, it has not been much of a hassle. But if you can fix this, it would be great!
Added: Now that I think about this, this could have a huge impact on people’s sync! If my hypothesis is really correct, you end up with a very poor, inconsistent, sync, if you have a comparatively large number of trash items. I normally only have a few, and GB worth of synced data in thousands of files, so most of the DB subfolders do not contain trash items. But if that ratio different, you might have a trash item in virtually every subfolder and syncing might be completely inconsistent to the point of failure.