> it does not go into any detailed analysis as to where that balance should lie
That's very much part of the point. From the article:
Without strict visual requirements associated with flat design, post flat offers designers tons of variety to explore new aesthetics – informed by the best qualities of skeuomorphic and flat design.
Well then this is just post-modernism applied to flat design. An amorphous ball of nothing that has no rules so do whatever you want. Want drop shadows in two directions, cool, cause we can do whatever we want now!
I'm not buying it. Post-modernism has been exposed as a joke by fake academic paper generators. Design loosed from it's moors is called experimentation, not post-flat, or whatever's cool right. Please, experiment, just don't claim you've re-invented magic.
That's very much part of the point. From the article:
Without strict visual requirements associated with flat design, post flat offers designers tons of variety to explore new aesthetics – informed by the best qualities of skeuomorphic and flat design.