Comment by rkomorn
I put a lot of the responsibility for the PMing failures I've seen on the engineering side not caring to invest anything at all into the relationship.
Ultimately, I think it's up to the engineering side to do its best to leverage the process for better results, and I've seen very little of that (and it's of course always been the PM side's fault).
And you're right: use what works for you. I just haven't seen anything that felt like it actually worked. Maybe one problem is people iterating so fast/often they don't actually know why it's not working.