Hi Gerald, Anchell seems to refer to the use of a 1% benzotriazole solution when modifying PQ developers for colder tones. He refers to the use of a 2% benzotriazole solution (and the ratio I quoted) for modifying MQ developers for colder tones. Of course, he warns there are no hard and fast rules, and that testing is required.
Perhaps I will also try to contact John Wimberley's regarding W130B which, as I described above, is identical to 130 except that the 5.5g/l of bromide restrainer is entirely replaced with .2g/l benzotriazole.
The large amount of bromide in regular 130 is interesting. Among other things it would help explain why 130 is reputed to work so consistently from print to print.