The new old fashioned planning method can be described as, "planning from within". This kind of planning uses the self organizing principles of hill towns and other village layouts to create places that arise from users actual movements. The set theory involved here is multiple
overlapping and always changing. It's taoistic in accepting an existing flow. It is bottom up.
The proposals for Paris are straddled between these two approaches. On the one had we see a new urbanist before and after sketch showing how reinstalling village fabric can restore an area:
On the other hand we have a new raised monorail to bypass the world below on the way to Tomorrowland like Robert Moses would love:
Then too, we have sinking rail lines and covering them with parks to restore links between neighborhoods by foot, which is restorative and looks at connecting. Also, there is a proposal to use the canals as places to invest so as to create places just as beautiful as those in the old city such that people will want to be in these new beautiful spots and wonderful living areas will grow from this.
Then again we're back to models with towers- just can't stop these from appearing:
And then, another green leafy urban new urbanist like sketch from the Rogers' office (long way from 70's for sure):
It appears as though the tide has turned against endless consumption though as sound practices such as establishing an urban limit as cities like Portland OR have done was proposed for Paris around the suburbs. As mentioned, removing industrial scars in the fabric and paying attention to neighborhoods and how they work- both proven strategies- were present.
The answer seems to be a dash of this and a dash of that with focus on enabling citizens to grow and adapt and change whilst every new piece creates a greater whole. The old city is a product of a bit of massive destruction of buildings for large boulevards that we enjoy. The setting of city limits is top down and limiting in a way but can free up the filling in with more attention to quality and infrastructure limits. The restoration of pedestrian play areas and movement can bring people out of their fortresses and cars to experience life more fully.
It's clear that the old city started as a few nice buildings and squares and a lot of slums which are now millionaire housing. This means it's all about creating great spaces for people to walk through and they will be filled with poor and then rich and new spaces can be created. It is only the constant attention to linking great existing spaces with new great spaces that will ensure a greater environment with the passage of time. Paris is this in the old center and can be this from inside out forever!