[blewis]

Judging from this:

In OmniFocus 1.1, we added a new "Archive Old Data..." item under the File menu. It will move older actions over to a separate database file that isn't synced with your phone. This way, you have access to your older actions when you need to refer to them back on your desktop, but your phone doesn't run out of memory.

In general, we'd recommend trying to keep the number of actions on your phone down below a thousand.

.....

It seems Archive Old Data was developed to make OF iPhone life better. I'd prefer that there be a setting that says "Don't sync stuff with OF iPhone older than...". That way, my desktop environment is untouched and things are made small enough for OF iPhone to work.

I archived my stuff this morning and I've already run into "missing completed" items in my search to figure out what happened in the past. Not a desirable side effect to being forced to size my database for OF iPhone performance problems.