"I didn't know you knew so much about writing"

A few days ago my husband and I were hanging out with a friend who asked us to look over a proposal he was writing. It seemed well-structured, but we went thru it line by line for style and grammar issues. After we got home, my husband said to me, "I didn't know you knew so much about writing."

Of course, he knows that I'm getting my master's in writing and that I teach writing. And I've read over his essays since before we were dating. I had no grand insights about our friend's proposal. I helped him revise a list to have parallel structure (which is complicated if one is a bit hazy on what constitutes a noun).

I might think that it was a handle on the "rules" of writing that caused my husband to observe that I knew stuff. But when I suggest guidelines for use in his own essays, he usually points out successful writers who don't follow the rules. Perhaps "rules" seem like knowledge--so long as someone else has to follow them.