Hi Eatibledotca!

I actually have been working on a pumpernickel rye bread similar to this on and off for awhile. It doesn't currently work for me due to the lack of gluten. Rye contains a starchy, gelatinous compound called pentosans which can aid in binding to a certain degree, but they can quickly become over activated and turn the dough into a gooey mess. Adding gluten flour would probably be a workable solution in this case. I'm looking into ditching the added yeast in future batches of the rye version and just having a dense, sour loaf like true German pumpernickel bread in the future. I'll email you my recipe notes on this bread so you can experiment with it!

Regarding this Flourless Sprouted Wheat recipe, I'm also looking into a possible wild yeasting of a portion of the dough then combining it with the rest of the dough to have a truly wild fermentation that leavens a little more aggressively. In this case, the wild yeasted dough would be "fed" fresh dough and embark on a more powerful leaven. Currently, I think the initial bulk dough rest/fermentation is inhibiting the added yeast, making it rather ineffective. Let me know if you find out any tricks! I'm always looking to make my recipes as good as they can possibly be.