82 is just dandy. The real trick is whether or not you can repeat it and if you picked up anything "off". Odds are that you're fine. I start looking askance at numbers above 85%
+1. When efficiency approaches 90%, that's when the beer starts getting thin and watery in my experience. 82% is just fine, and in fact is pretty much my goal -- high enough, but not too high.
Wonder if you'd care to support your theory with a little chemistry...
You see, that's just it -- chemistry and science don't matter so much, and in this case maybe not at all. In my opinion, the only thing that matters is TASTE. And taste, of course, is somewhat subjective, which is another piece of the whole puzzle.
I can get >95% efficiency. I have done so once or twice, and I've proven to myself that on my system I can hit >90% with ease. BUT... am I making really good beer that way? Some people will say, ooh, ah, he can get 95% efficiency, I should try doing that too. But you probably haven't tasted that 95% eff beer, either. Well, I have. And? My taste buds aren't quite sure yet, but are leaning more towards the opinion that uber-high efficiency is NOT such a good thing. I think my beer tastes better if I purposely try to get less sugar and more of that non-sugary grainy stuff in my beer than if I'm just extracting maximum sugar. Because in theory, sugar by itself is flavorless. What I mean is, the only flavor you really get from any sugars is from the impurities therein. Same holds true for brown sugar, molasses, honey, etc. It's the impurities that give these sugars all their flavor. What impurities? Well, in malt we have things like husks, tannins, starches, proteins, melanoidins, whatever, in addition to maltose, dextrose, sucrose, fructose, you-name-it-ose. So, I suppose the theory goes, if you're squeezing every possible molecule of sugar out of a minimum amount of grain and hitting 100% of possible efficiency, while you might not be turning out pure white flavorless sugar from such a process, I think you are indeed actually taking your beer a little closer toward the flavorless range. You've got more sugar and less impurities because you're doing such a darn "good" job at extracting all the sugars out of your grain. See what I mean?
I'll say it again -- more experiments are necessary. But I have a hunch that I'm right. I'm just too damned lazy, especially to try to prove it to a highly technical and often downright geeky population of millions of homebrewers and beer lovers that absolutely do NOT want to hear that they should NOT be striving for maximum efficiency, and that what they really need to strive for is consistency and thereafter should shut up and sit back and revel in their seemingly crappy 70% or 75% efficiency. I argue that bigger is NOT better. But a lot of people can't stand to hear that. They have to keep tweaking, and tweaking, and wondering what they're doing wrong. I say that as long as a brewer is consistent, and their beer tastes really good, they aren't doing anything wrong, and have no reason to tweak or try to fix that which is NOT broken.
The best advice I can give anyone on anything related to brewing, especially to all the novices out there, is: Take all those old brewers' tales and rules of thumb, everything you've read about in old books... and throw them all out the window, and figure out the truth on your own. With just a few batches experience, you'll come to find and agree that SO many old rules of thumb are SO wrong that it ain't funny -- it's downright hysterical!! In the end, the only way you're going to find out the truth is to seek it out on your own, formed by your own experiments and your own experiences, with the subjective topic of "taste" verified (or not) through objective opinion -- BJCP is a good place to get some assistance, but don't stop there, either. Read a lot, but take it all in with LOTS of grains of salt. Because in the end, we need to figure out what works for us, ourselves, and discover our own truths. Everyone else be damned if they try to tell you you're wrong based on who knows what, when you know the truth based on your own experience.
It's obvious you've put a lot of thought into this. But I gotta say--once or twice? You've hit 95% efficiency 'once or twice' and the resulting beers have been less than stellar--though your taste buds are not 'quite sure yet.' With respect, that's a pretty thin foundation upon which to build such a big theory.
You say you prefer less sugar and more of the non-sugary stuff. That's fine. With your mash temps, your pH levels, your water chemistry--you determine the profile of your mash, your wort. If you want a higher proportion of dextrins, you'll mash at a higher temp. But it seems to me that a higher efficiency is just getting more out of your grist. Same ratio of fermentables to unfermentables, just more of both.
You write:'The best advice I can give anyone on anything related to brewing, especially to all the novices out there, is: Take all those old brewers' tales and rules of thumb, everything you've read about in old books... and throw them all out the window, and figure out the truth on your own. With just a few batches experience, you'll come to find and agree that SO many old rules of thumb are SO wrong that it ain't funny -- it's downright hysterical!!'
I think you're on even shakier ground there. There's an old adage about not reinventing the wheel that I think may apply. In the ten thousand years we've been brewing we've learned a thing or two. 'Brewers' tales and rules of thumb' survive because they are valuable; they don't if they're not. Like evolution. Why on earth would you tell new brewers to 'throw them out the window?' What are you, a book burner?
And it's not just the methodology of brewing that's been formed by evolution. Our beer styles have come down to us through the ages. 10,000 years of development and tweaking, 10,000 years of test marketing. 10,000 years of learning what we like and what we don't. The styles aren't rules and regulations, they're valuable data about what works for us. There's have been a lot of changes in home brewing since I started 25 years ago, and most of them have been great. But two I consider unfortunate have been 1) the move toward ever faster brews (shorter mashes, batch sparging, etc.) and 2) the seeming disregard and often downright disdain for brewing lore. It seems somehow a uniquely American arrogance--10,000 years of testing, tweaking, refining? Screw that--I LIKE 100 IBU beer! Style guidelines? Fascism!
Now I'll get off my soapbox.