The main point, as I understand it, is that the authors suggest that you create a sort of a full-reserve system for individual deposits within the standard fractional-reserve banking framework that's in place for institutions. Apart from the usual issues that full-reserve banking exhibits, the main problem is that the setup they propose is profoundly unfair. Why should I, as a retail depositor, be entitled to a lower yield than an institution? As always happens when artificial abritrary constraints are imposed, the mkt will quickly find a way to circumvent these rules and we will be back to square one. I will be able to elaborate once I re-read the piece again.