Of course, that was my inner asshole talking. The Gottman book mentioned the toilet seat thing as a very specific example of how a husband can fail to let his wife influence him. It takes no time and earns you kudos. Why wouldn't you do it?
So I tried.
And guess what? It's hard. I have real trouble remembering to do it. Learning a new habit after 40 years doesn't come easy.
My solution? Take one of the kids crayons or dry-erase markers, and write on the underside of the toilet lids, "DOWN." Now I've got a reminder in my face - so easy to remember, in fact, that The Wife didn't even know I had done it for a week. (And when she did find out, she thought it was cute, like, Awww, he's really trying.)
After a while, the cleaning lady erased it. And then, longer still, the habit came back. One day, after I'd noticed The Wife's snippiness factor increasing, I wondered - have I been remembering the toilet seat? And, after checking: no. No I had not.
Time to write on them again. In fact, think I'll double-check them right now.