Sharp-eyed reader DC emailed me, pointing out an assumption I made in Rule #11 of my last post: I assumed you would know that I was referring only to prepositions found in titles. I knew what I meant and assumed you would all be mindreaders. This rule applies only to prepositions in titles—anywhere else (except for the first word of a sentence), they are all lowercase.
I apologize for the confusion I may have caused. I broke my own rule: never assume anything.
As always, feel free to write me with questions, corrections and suggestions. I’m eager to hear from you.