It's possible that they change for different formats. Sometimes they use a slightly different emulsion for different formats. But I think it's mostly due to the amount of chemistry used. Like for 120, which has the same surface area as 35mm (36 exp), but essentially double the amount of chemistry. So the amount of effective elements present is greater when compared to smaller formats.
As for the times given by CS1, I know his times for 400 were pretty close to optimal. but we're dealing with an experimental developer that is based on non-optimal developing agents that have not been calibrated and tested in any way, so results will vary.
The only thing for sure, the Robusta coffee used is sure to give you heartburn no matter what.