Why doesn't my whole wheat dough pass the Poke Test?
The "spring back poke test" is a function of gluten content. Whole-wheat doughs have a hard time building gluten networks, because the sharp edges of the bran cut through the gluten strands as you knead. In general, you should never use more than 50% whole-wheat flour in a standard bread dough. Cook's Illustrated successfully increased that to 60% by soaking the whole-wheat flour in milk for at least 8 hours before making the dough, and using bread flour instead of all-purpose for the other 40%.