Wow, I have definitely gained both insight and validation from these
responses (even though my 'example' was not meant as a plea for
advice!).
Conclusions:
1.) I should have been more honest, and flat out said, 'I just
don't have it in me to deal with this right now, so will you?'

2.) But if I had just said that, and my husband went ahead and
forced the soap-thing right then, I would have stopped
him.

3.) The actual problem that I need to address with my husband is
this: It's exhausting to be in charge of all the 'behavior
modification' with four boys; I need help.

4.) The bigger problem (harder to solve) is that although I need
help, I am not willing to watch my husband (who IS an
amateur at behavior modification, and tends to stick to
ideas even when they don't work)... I'm not willing to watch him run
roughshod over the boys in a fit of anger. I'm not trash-talking him,
I'm stating a fact: when something doesn't work, he just gets mad and
tries to force it, and if he can't force it he accepts defeat.

5.) Because of # 4, it is ridiculous to expect #1. So # 3 is
how it will stay.

Final conclusion: Yes, I was a bitch, but I forgive
myself. Sighhhhh