<<Disclaimer: Verify this information before applying it to your situation.>>

Here are the responses to my query on secrets to homemade gf breads:

1.  I use 2 cups tapioca starch and 2 cups either white/brown rice works
well for my bread recipe with 2 tsp xanthan gum.

2.  I never had any success with Bette Hagmans mix and have since
learned another mix that uses 2 cups white/brown rice flour, 1 cup
tapioca flour.  It's no longer gritty.

3. My gf flour mix is 1 part garbanzo bean, 1 part tapioca starch and 1
part cornstarch.  I used 1 cup of that mixture plus 1/2 cup of mochiko
or sweet rice flour.

4. When I am trying out a new or modified recipe, I start by dividing
the recipe into 1/4 the amount and experimenting with smaller amounts.
Then I make one change to each of the four recipes and compare the
results.

5. If the dough is too thick, add a tablespoon more milk at a time until
the dough texture mimics what you'd expect.  Try adding another yeast
packet or 1 TBSP baking powder.

6. Consider using a lighter flour blend with less rice and more starchy
flours.

7. I am lucky to live in the same area that Bette Hagman lives and
attended a GIG meeting where she gave a lecture.  The important
chemistry that goes on in yeast breads depends on the amount of protein
contained in the dough.  This is why so many gf recipes have added eggs
and why the new bean flours are finding so much acceptance.  Wheat flour
has almost twice the amount of protein as does rice, so you need to add
a flour or protein to replace the missing.  Bean flour or nut meal
and/or eggs will help.

8. For a cranberry type bread, I use a ratio of 1 cup rice flour to 1/2
cup each tapioca and potato starch flours (obviously increasing the
amounts depending on how much gluten flour is called for), with the
addition of the basic rule of 1 tsp. xanthan gum per cup of flour for
breads.  It makes a world of difference if you sift the flours.

9. I just use the Gluten Free Pantry's "Favorite Sandwich Bread" mix.

10. My only secret is -- don't.  It does not work unless you make
something like banana or apple bread.  You have to make too many
changes.  The dough cannot be thick enough to knead or you get cement.
The quick breads turn out fine with few changes.

11.  Use more moistening if the bread dough bakes too thick.  Let yeast
risen dough only rise once, and not to a full doubling in volume.  If
crust bakes too fast, cover with foil (possibly for only part of time in
oven).  If a soda bread tastes really bad, like pure soda, use one-third
as much baking soda as the recipe calls for, and instead substitute soda
pop for hafl of liquid (and for part of sugar if a sweetened pop is
used).  Mix liquid and flour mix together (but not any leavening) and
let sit over night to soften the flour.  (Helps a lot if rice flour
grittiness is the main problem).