Honestly speaking, I myself don't know if my question has been answered or not as I haven't worked with HU ever and that's why I'm following this thread. Additionally, I myself don't know if I have asked a correct question.
Information you shared is definitely valuable as I would now refer some help files and would understand the logic behind HU functionality keeping your suggestions in mind. Would further run few scenarios in the sand box and see what do I get.
Thank you for sharing your views Mr Craig 
ntn