It takes away the differing values embraced by various functional groups and encourages the connection between projects and strategic goals.
However, you need to get all parties to buy-in to this way of doing things. If the approach is not applied consistently then the results will not be equitable and the process will quickly gain a bad reputation. One way to success is to have a neutral central group like the PMO control it.
You also have to be careful, as the article points out, of groups “gaming the system” – looking for ways to get their projects to the top of the list. One of the common ways is the misuse of mandatory or regulatory projects – this needs to be carefully policed.
Overall though, this type of portfolio management approach will drive consistent investment decisions that are linked to your strategic goals.