I'll start by saying you are my kind of knucklehead.

I'd be willing to bet that I've edited more posts than not after publication. For what ever reason I seem to be unable to correct every error until it's published.

That said, I have deleted one post. Back in the days of pure MarkUp I used a text editor to get the thing right, with every post. Depending on the error I'd correct the original in the TE or just correct it in the post edit feature. One day I corrected the original (my preferred method) and then hit post instead of edit. I had a duplicate post. I deleted it and left just enough text to explain my knuckleheadedness. Ah, well. Only once, though :)