I get better efficiency with full volume BIAB than I did with traditional double batch sparge in a converted cooler mash tun! I think other ex 3V brewers will weigh in here and also confirm that they get better efficiency with BIAB than they did with more traditional methods.

---Todd

Like the way you are thinking Epithemeus ,

As Todd mentioned, the truth is that you should actually get a higher Efficiency into Kettle (EIK) with BIAB than traditional. I don't like putting numbers out on the net unless they are well-researched but here's a few thoughts for you. When I moved to BIAB, my EIK on say a 1.050 brew went up by 5%. I did one side by side of BIAB and three-vessel and this also came up 5% higher.

I actually don't think this is the question you are really thinking on though. I suspect what you are really thinking is, "Is a pure BIAB (one that is mashed with all the water) more or less efficient than say a Maxi-BIAB where all the water needed for the brew was added in two stages?"

Is that more along the lines of your thinking or am I guessing incorrectly?

If so, the current answer I would give you, based on side by side brews I have done etc, is that there is no difference between the above two methods. The basic logic and reasoning behind this is more simple than you are currently thinking but it is very hard for our brains to accept the simplicity.

If you are interested in what causes this mental 'struggle', have a look at some of my posts that contain the keywords, 'washing machine.' They'll probably be long but I think will interest someone like yourself who is obviously putting some good thinking into this area.

Good on you ,
PP