Our Aha hierarchy is built out where are portfolios are fairly separate but still will have some dependent work. It would help us track those dependencies a lot clearer to have the rollup allow product initiatives to roll up to portfolio initiatives outside of their own. It also allows for more discreet reporting.
We would also benefit from this functionality. We have multiple teams who work across products and the structure as it is now we will have to create artificial initiatives for the sake of reporting and connect using the "related" functionality or another less elegant method like tagging.