The buckwheat article did mention that the crush could be .5mm without losing too many fermentables. I would also think that adding rice hulls would help create a filter bed to avoid a stuck sparge. My impression when reading the articles was that the buckwheat experiment was more of a "real...
The IB article for mashing a full Buckwheat grain bill can be read here: http://onlinelibrary.wiley.com/doi/10.1002/j.2050-0416.2006.tb00708.x/abstract
They also have done an article on mashing 100% Proso Millet: http://onlinelibrary.wiley.com/doi/10.1002/j.2050-0416.2010.tb00410.x/abstract...
