Heard that too. Really just splitting hairs, though. Where BIAB ends and MIAB begins is blurry. Many people who use BIAB use a second vessel for a dunk sparge (which would be called a batch sparge in coolers), and stir the grains just as you would in a cooler.
Relax. No need to get worked up about semantics here.
I heat up strike water in a pot, add a bag and pour grains in, stir, and rest until conversion. Sometimes I also infuse hot water or heat for a different rest. I also remove the bag, and dunk in a second pot with hot (or sometimes cold) water for a sparge to extract more sugars before adding that wort to the boil pot.
Sounds a lot like batch sparging and mashing in a cooler, except I use pot(s) without a valve and can direct heat if I wish.
The line is blurry. I would call what I do BIAB, but some would call it something else, I guess.:fro: