I said I was going to try it out, and I did today. I posted a bunch of pics here
, and the process is explained in detail here
I used my 3-tier stand, but since CRDFM only requires 2 vessels I only used the bottom 2 tiers. I placed the MLT on the top and the BK/HLT on the bottom. The Brutus 20 uses a single tier design with 2 pumps, I just let the MLT gravity drain to the BK and used a pump to recirculate back up to the MLT.
I brewed a hefeweizen with pre-crushed grains from AHS (the BC is still under the tree!) I usually get ~ 65% effeciency. Today I got 58% efficiency, but I was also 1/2 gal short, and sometimes I'm a little lower on wheat beers anyway. More total sparge water might have helped a little.
I recirculated for ~ 35 mins. That was enough to reach specific gravity equilibrium between the MLT and BK.
The overall work involved was slightly less than batch sparging. Once the sparge started, you just let it recirculate until you're done. I didn't have to fiddle with the flow rates much - only 2 or 3 adjustments. I just tried to keep the BK within a qt of where it started, which was easy with my thermosights.
It DOES require at least one pump (2 for single tier setups), but makes up for that by eliminating the HLT and its associated burner and plumbing.
It required slightly more time vs batch sparging, maybe an extra 10-20 mins, but was still less than or equal to fly sparging.
I probably lost a little efficiency, but it's hard to tell how much. You really need to do identical brews to see for sure. I've never been a super high efficiency brewer anyway, but those of you who are probably won't like that fact. I'll do it again after I incorporate my Barley Crusher and see how things turn out with an all-barley grain bill.
Overall, I think this is a fairly simple, sound, viable process. For those who may be considering a stand with a small footprint, this may be something you want to think about.
Comments welcome. I know colplink (Brutus 10/20 creator) lurks here. Maybe he'll chime in.