I tried that one Tetsu Kasuya recipe more or less (I wasn’t too concerned with timing and I used a larger dose than is quite practical and had to fudge by adding a bit more water during the final drawdown. I also used a different ratio.) It did a pretty good job with Colorfull’s Wilton Benitez decaf, which is a coffee I have no complaints about but which I have not been getting the most out of, perhaps.
For my personal brewing, this recipe might be unnecessarily complex, since from a flavor standpoint, I think I can get similar results with bypass recipes more easily. Probably this recipe stands out for folks who need more body in their coffee, something that as a tea person I don’t really ever miss.
Next time I should try just doing an immersion soak and single drawdown, since I haven’t done an immersion brew in living memory.
I have not yet tried the Mugen swap, but I have a Mugen so I will definitely do so at some point.