In my earlier post in this thread, I had confessed to not having made a Chemex brew in some 3 years.
So I've made a Chemex every morning for Trish and me for the past few weeks. I have a few thoughts based on this experience. FYI, I'm using a Ditting KR1203 grinder (yes, at home, which is what happens when you're 'between stores'), a Takahiro pouring pitcher (like this one I gave to Aaron), and an 8-cup Chemex with the big folded paper filters.
I've been frustrated for some time about the lack of controls on manual-pour brew methods. This is somewhat silly to say, but my point is that dose/throw, grind, and turbulence are really the only useful control points you have. With a Melitta or ceramic filter-holder style brew, I always crave a way to slow down the brew through the bottom of the filter, in order to extend the brew time without having to grind finer. In fact, I plugged one of the two holes on our Beehouse drippers for this reason, and I like the brew much more now.
What I'm finding by tweaking the brew every morning on the Chemex is that I am happy with a 20 oz. final volume in about 4 minutes... that's it. I am not happy with the taste results when trying to brew more than that, and I'm not happy with the taste results when trying to brew less than that.
Luke, my grind is now such that the brew is complete at just over 4 minutes (I'm at about 42 grams for the 20 oz as well... "on the button"), without having to pull the filter toward the end anymore. I'm also pre-measuring the water before putting it in my water kettle. Have you tried a japanese-style pouring pitcher?
So as far as Scott's original point is concerned, I'll stick to my original feedback: that there are perhaps reasons to "hate" the Chemex, but that most any brew method will present similar limitations. Without claiming anything "new," I think that every manual-pour system actually has a single optimal yield (brew volume)... something that I'd reckon using a refractometer would support.
Over the past couple years, I've been quietly begging folks who are involved in the creation of such things for a manual-pour filter holder with an adjustable final 'hole' aperture. This would theoretically allow one more control point with the otherwise manual system that would somewhat separate brew-time from grind/dose, allowing for an extended brew time with a coarser grind than otherwise. For those with Beehouse drippers, try plugging one of the two holes and grinding coarser. We've had great results. To my earlier point, this will depend on your target volume.
Just a little Saturday morning brain-dump, fueled by a great Chemex brew of Barismo Kenya Kiandu.