Just ran two experiments with my new bottle of CLR.
First, ran a couple wet patches through a 223 bore with ~ 3000 rounds. The barrel had been cleaned using Boretech C4 and Copper Remover.
There was 0.0 black/brown on either of the patches with CLR.
Second. Cleaned a different 223 barrel that had just been shot in a match - 88 rounds.
First 20 patches all had CLR on them. Twice during the 20 patches, there was a 5-10 minute wait/soak time. After the 20th patch with CLR, pushed three dry patches through and started using Boretech Eliminator.
Through patch 12 or so, the patches came out solidly coated with black material. The 20th patch with CLR still had some brown/black stuff on it.
In using the Boretech eliminator, there was 5 or so minutes of wait time between sets of two patches. In addition to the blue, there were areas of black/brown that kept decreasing in width. After 7 sets of two patches with Eliminator [with one of the wait period a couple hours], there was no more black/brown stuff on either a wet or dry patch.
After there was no more black/brown stuff on the patches with Eliminator and three dry patches, passed two patches with CLR - no additional black/brown stuff.
My conclusions:
Using CLR can replace using a bronze brush in removing carbon [when I do use a bronze brush, I've found it takes ~ 15 strokes], but is not more effective at getting the carbon in the corners of the lands/grooves than Boretech Eliminator.
Bonus finding:
In the past, I've cleaned a couple barrels with Hoppes 9 - including brushing. Then run patches with Boretech C4. The patches with Boretech C4 came out almost completely covered in black. => Hoppes just isn't much of a bore cleaner.