Triple raised doughnuts

Local doughnut shop (Gibson’s  in Memphis, best on the planet) has said that the secret to their doughnuts is that they’re triple raised.

i know that they also use old-fashioned cake yeast.

But if you were going to alter a traditional double-raised doughnut (i.e. bulk ferment then firm and prove) to make it triple raised, what would you do?

Recipe in the new Cooks Illustrated looks like a good one to start with, but generally... I’m looking for suggestions.