I always did think that brewhouse eff was based on fermenter volumes, and really the only people that should be interested in brewhouse eff is accountants since that is about minimising losses (dead-space etc.)
I checked out the HBT wiki and they agree (not that any Wiki is a solid agurment to stand on
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If the HBT Wiki says that, it is wrong. I think I have seen that before, and didn't bother trying to get it corrected. I think it directly quotes Braukaiser, then within a couple of sentences contradicts his 'to the kettle' definition of Brewhouse Eff (which is based on century old German brewing texts).
This is a fact: Brewhouse Eff has been 'to the kettle' for centuries. BS was almost single-handedly responsible for re-defining/obfuscating the term as 'to the fermentor'. Very few brewing SW packages use 'to the fermentor' for eff. I spoke to a couple of the newer package designers that chose to blindly copy BS methods, and they both did a big self-headslap when I explained the issues with it.
Using 'to the fermentor' for batch size is another BS issue. It should also be 'in the kettle' to make sharing recipes easier. That is why Jamil always uses the '6G batch' (5.5 to the fermentor). Setting a secondary goal of what makes it to the fermentor is fine, but 'in the kettle' is the only single number that makes sharing/scaling possible.
Thinking about it - taking the efficency at either the beginning of the boil or end of the boil it should be the same (no sugar disappears). There would be no difference in mash/laueter eff compared to brewhouse eff if they were both measure at the kettle. I do agree (See my next point) that BS should not be using brewhouse eff and should be using M/L eff.
I'm not sure what you are trying to say. Mash (conversion) Eff * Lauter Eff = Brewhouse/Kettle Eff. I am not referring to the BS version of 'Brewhouse', and always try to specify the 'kettle' (proper) or 'fermentor' (idiotic) version I am talking about. This ultra-clarification is only necessary due to BS and their ridiculous redefinition of Brewhouse Eff as 'to the fermentor'.
I never talked about pre-boil vs. post-boil Kettle eff, for the reasons you cited (they are the same); however, your use of MLT Eff needs to be clarified. Mash eff is the same as 'conversion' eff, and Lauter eff is how much of the converted sugar is transferred (lautered?) 'to the kettle'. Mash Eff * Lauter Eff = Brewhouse/Kettle Eff. Knowing the component parts of traditional Brewhouse/Kettle Eff makes real-time and post-mortem tracking of brewhouse issues easier. You can check your mash eff before lautering to see how things are progressing, or to find out where things went wrong.
But is it a defect in the calculation or a defect in how they explain/use it? I would argue that the calculation is correct but it should only be displayed for information.
The bastardization of the terminology by BS is what is undoubtedly incorrect- historically, Brewhouse efficiency has had nothing to do with anything post-kettle, for good reason. The BS design decision to use 'to the fermentor' as a brew-side metric was simply an ill-conceived choice. I believe the BS designers now know this, but there is no easy way to switch metrics without upsetting a lot of clueless users.
There should be a seperate (changeable) value for mash/lauter efficiency.
Now you are opening up a whole can of worms. You can't specify both a kettle (or further downstream) based efficiency, and specify an adjustable mash and/or lauter eff. They are inter-related. This is the crux of the issue with BS using 'to the fermentor'. If you change your trub value, your mash efficiency is auto-recalc'd. This is because you also need to change your 'to the fermentor' efficiency since you changed the volume going 'to the fermentor'.
I ridiculed the fanboys on the BS forum when they defended 'to the fermentor' as a perfectly valid method. I pointed out how BS's marketing schtick is 'Why do the calc's yourself', yet the one number BS makes you supply has to be hand calc'd if you simply change your trub value. This is due to the poor design choice to use 'to the fermentor' for eff. Magically, a few days later a new calc tool appeared on the BS website as a workaround. No real explanation or announcement about why/how to use it, though. A hack job if you ask me.
This would make sharing recipes easier as you say since you don't have to know anything about the other persons setup apart from how effecient their MLT is and they will tell you that.
So reading that back, I actually do agree that BS should make changes to the program to make it more user freindly to share recipes
Combined MLT eff = Brewhouse/Kettle Eff, as I stated earlier, which I think you see the benefits of now. You probably now also see the uselessness of 'to the fermentor' efficiency for anything related to actually brewing. It is a number for the bean counters in the business office only.
To burst your bubble even further, since I see you BIAB, BS is completely worthless when it comes to BIAB and batch sparging. The numbers are garbage, unless you supply with the exact Brewhouse efficiency for that particular recipe. BIAB (and batch sparge) are a fixed game, and should be based on conversion efficiency, and lauter eff (true grain absorption only for BIAB). The SW should tell you what your Brewhouse eff is for these lauter styles, not the other way around.
There is a workaround for doing BIAB/batch sparge in BS, but I find it easier to use the Aussie BIAB-calc, and BIABacus spreadsheets.