I had a couple of missed schedules this morning... When I went through and tried to get them to post, disabling Twitter Tools was the step that made them go through. Going over to Twitter, it looks like they were overloaded, hence tweets weren't posting.
Is it possible the overload of twitter itself was causing the posts to miss their schedule? IE, there was an error in the running of twitter tools that caused the cron to stop running, so the posts didn't post at all?
If so, is it possible to disconnect these two so posts will still post even if twitter tools fails to tweet the post?