Yep, you hit it on the head! (Or multiple heads, as the case may be.)

So annoying that our bodies work against us in this. Interesting, but annoying.

You're right about mixing things up, too. After I made this post, I read about "zig-zagging" your calories. If you're supposed to eat 1,600 per day, instead use the total for the week and have some lower and some higher days, so it fools your body. I'm going to try to do that.