The resolution and light gathering requirements should be pretty easy to analyze on paper to answer the question "will this ever be usable in practice"? The fact that this isn't done could suggest that the answer really is no, so the authors omitted it.

I'm sceptic that it will ever be even close to usable assuming sensor tech wont improve much and we don't reach some breakthrough in optics, i.e. bending light without huge heavy chunks of glass.

This experiment with huge flash guns and short distances is essentially like identifying the moon in an eye reflection and dreaming of doing deep space imaging the same way. The physics just don't allow it.