Don't worry about this Bill for a few reasons...
1. Dark grains lower the pH less than crystal grains (latest knowledge).
2. In BIAB, you are full volume brewing (mashing and sparging simultaneously) so the grain bill has far less effect on the PH.
3. There is
a difference between whether you just steep or mash and steep your grains but this is a new phenomenon and we don't have much info on it. You should assume however, unless told otherwise, that, in an all-grain recipe, all of the grains are mashed.
[NOTE: You'll see in BIABAcus PR1.3T, maybe before, that it allows the user to type in if they choose to steep a specialty grain rather than mashing it as well.]
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