My wife had finally achieved the Holy Grail of 100% whole wheat bread.
I'll post the recipe below.

Recently, it's not rising nearly enough. It's still fluffy, not
dense, but it doesn't rise nearly as much as it did.

We're wondering if it's the low humidity of winter.
If so, is there an adjustment to be made?

By the way, we've added ground flax seed and oats, and this bread
absolutely rocks.

2 Tbs sugar
1 Tbs active dry yeast
3/4 cup warm water
1/4 cup milk
1 Tbs vegetable oil
2 Tbs gluten
3 cups whole wheat flour
1 tsp salt
1 egg, beaten



1 In a small mixing bowl, dissolve the sugar and yeast in warm water.
Let stand until creamy, about 10 minutes. In a large mixing bowl,
combine the yeast mixture with the milk, vegetable oil, gluten, 2 ½
cups of whole wheat flour, and the salt; beat well. Add the remaining
flour, ¼ cup at a time, stirring well after each addition. When the
dough has pulled together, turn it out onto a lightly floured surface
and knead until smooth and elastic, about 10 minutes. Oil a large
bowl, place the dough in the bowl and turn to coat with oil. Cover
with a damp cloth and let rise in a warm place until doubled in
volume, about 1 hour.
2 Grease two 8x4 inch bread pans. Deflate the dough and turn it out
onto a lightly floured surface. Divide the dough into two equal pieces
and form into loaves. Place the loaves into the pans. Cover with a
damp cloth and let rise until doubled in volume, about 40 minutes.
Meanwhile, preheat oven to 400 degrees F (200 degrees C). Brush the
risen loafs with lightly beaten egg. Bake at degrees F (200 degrees C)
for 30 minutes, or until the bottom of the loaf sounds hollow when
tapped.