Sorry for the misinterpretation. I wasn't trying to fault ML's logic, and I actually agree with her. Her thoughts made me realize that the term "undivided" is subjective. Optimism's original scenario was watching his son's baseball game with his GF. In the midst of the game, they found lots of time to focus on each other. The point of UA is to give yourselves an opportunity to make deposits in each other's LBs, and that's what optimism and his GF were doing. Some people can do that in the presence of a ball game, others can't. It's subjective.

I don't think it matters so much what the precise definition of "undivided" is. What matters is whether a couple is making enough LB deposits to satisfy both of them.