Perhaps he was talking about the double mash that Randy Mosher described in his last book. That is where you collect the runnings from one mash, then use that as the mash water for a second mash (with new grain).
Speaking of high gravity efficiency, on my last batch of Belgian Strong Dark I was shooting for 85% (which I have been getting consistently) and a 1.090 OG. However, on this batch I got an OG of 1.106 which would equate to a 95% efficiency. I did not believe it but I calibrated my refractometer and my hydrometer matched it. I don't think I mis-weighed the grain either. Collected volume was good too. I did have a 4 lb sugar addition but I accounted for that in the recipe. Perhaps Pro-Mash is not calculating the sugar gravity points correctly.
Brewing since 1989 - BJCP National Rank
Conditioning: Burton Ale, Belgian Quad, Old Ale
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