I wouldn't be surprised if he attempted some lame version of the homework later today That is what I had in mind, even last week.
I suspect Mr. HW has a lot of internal thoughts that he does carry through on his promises, so will attempt to do the homework.
but I am not holding my breath in that regard.. The way I look at the situation, don't you play the dutiful parent role and let him play the how-does-he-get-out-of-this-kid, role.
I agree with LFL on the accountability vs. not pushing too hard. Trouble is I don't push when I should sometimes.