Once again TwitterTools started screwing up on the digest feature. I know it’s “experimental” but it seems to break so easily. By itself it randomly stops working. Switching to engine makes the code break and appear in the pull-down menus.
So, now I’m using TwitterTools to cross-post to Twitter only, with Twitter Digest to make the daily digest. The “Exclude category” ad-on for Twitter Tools should allow the two plugins to work side by side without getting into an infinite twitter-posting loop.