Stage Gate and Portfolio Management - continued

How does one resolve the overlap between a gate meeting and a portfolio management decision? Going back to basics, the purpose of a stage gate process is to manage the risk on an individual project. A portfolio management process manages the balance of risk and other attributes across the set of items that make up the portfolio.

So... portfolio management sets the target levels of risk, etc. for different parts of the portfolio. The gate review then assesses the project against the target levels and bases a Go/Kill decision using a 'must meet' comparison. A Kill decision would be an input to the Portfolio Managment process - removing the project from the list of candidates from resourcing.

A Go decision is also an input to the Portfolio Management process, confirming the project's status as a candidate for resource prioritisation.

Should be easy? So why don't more organisations do it?