I would agree with most you say, apart from the last paragraph. Surely the people who have made the allocations in the first place realise what they need in housing stock, so a reevaluation would not be too difficult I would have thought. Then a certain amount of putting people in the right size accommodation, then build what your need. I'm not suggesting you get it better than 70% accurate. If you don't follow some process what would you consider a satisfactory outcome. I follow your analogy but I think maybe you want an evening class in mechanics, sorry its full, you can wait till the next course or there is one in the next village/town available.