This morning I had another system update on my Incredible. Figured it was a patch for yesterday's Gingerbread update and blindly hit install. It failed, leaving who knows what in the application data directory and I had to clear unrelated app data again to get below the warning threshold so my mail would sync.
As much as I like this phone, the lack of response from both Verizon and HTC on this issue (which has affected people since the phone launched) is pushing me away. Rooting will eliminate the issue, but shouldn't companies support their products with more than "a hard reset will take care of that."
And that is why I want my next phone to be a Nexus and I'm willing to wait for it.