LOL! Yep I know what you mean.
Weighing the grain yourself is no excuse though

. I once had a guy that sent me a lot of correspondence on why his one brew got some shocking efficiency figure. I went through the usual suspects and he had weighed the grain himself as well. It had me really dissapointed and totally confused until a few weeks later he wrote back and had found the plastic container full of carefully weighed out base malt that he had forgotten to add to the brew! (It was not all the base malt but about half of it.)
I must say that we brewers make a lot more mistakes than we think or aware* of and this is understandable as there is a lot of measurement etc involved. I love the brewers who publish when they make a mistake as it teaches us all.
* I often brew with a fellow brewer. I reckon that about ten percent of the time we pick up on an error that the other brewer would have sworn they had correct and this is during the sober part of the proceedings!!!
Those of us who measure our own grain should probably have a double-check system but none of us do!
One great thing about BIAB is that there are less ways to bugger it up. The efficiency is very good very good as your figures and many others show. If you have a good recipe, good cleanliness and a good thermometer then it is very hard to get a crap beer

.
I realise now that no matter how confident I am, my own figures on a single brew are totally unreliable. I now know though my averages and am very confident in them. If I weigh my grains somewhat correctly and have my correct initial volume I am assured of a great beer thanks to mates whose recipes I have stolen

.
In other words hashie, don't worry about finding causes to explain one measurement oddity on a single brew. If the same thing happens on the next two brews then I am all for an investigation!
Cheers to you hashie,
PP
P.S. I think I wrote on here a while back about us all contributing/combining our figures. I probably should start a new thread on that???
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