I think the answer is yes and no. True, letting the friends see the mess will put the focus on him, but it will probably trigger a fight. He will take it as an attempt to embarrass him. He could see that as force or manipulation.
I guess I should have stated that part of my comment includes the assumption that money is a critical factor here. Since he plans on doing much of the work himself, I am guessing he is sensitive to spending. Usually this is a pet peeve for men.
The flip side is that for Annette to leave the leaves on the ground means she has to endure the embarrassment, as you say, but also compromise on her wishes and values. Setting boundaries all comes down to personal integrity. She needs to hold the line on that, otherwise she will become angry and resentful. She should not have to compromise her wishes just for his laziness.
