Ron, we may be talking at cross purposes and perhaps it should be a different thread except - Roger Hick's comment that "In some ways, those who bemoan the passing of the ‘good old days’ are, for once, right." talking about the removal of Cadmium from Warm-tone papers.
We can only go by what Agfa and others paper manufacturers said at the time, but it was EEC (now the EU) directives that forced Agfa to reformulate Record Rapid (Portriga). There are many references to various chloro-bromide papers and the big differences between the current cadmium free versions and the older cadmium loaded versions, these can be found in books and articles as well as on the internet.
Agfa, Kentmere, Forte and Foma all used Cadmium in their warm-tone Chloro-bromide papers. Ilford didn't make a warm-tone paper for quite a time and by the time of Multigrade Warmtone's introduction the EU Cadmium directive was in place. Ektalure was the last Kodak paper to include cadmium, it was certainly available in the late 1980's and early 90's, I don't know if they eventually took out the cadmium before production ceased in the late 90's..
A few quotes:
Tim Rudman: "The Kentona, Art Classic, Tapestry, Luminos emulsions changed when EEC laws restricted the use of cadmium in the manufacturing process. Although these papers were fine art warm tone general papers they had unique properties when Lith printed and then selenium toned. Although the new cadmium-free versions of these papers both print and Lith print very well they are quite different to the old and no longer have the multi-colour potential . . . . . "
Roger Hicks: "Unfortunately for photographers, though fortunately for the environment, cadmium was dropped as an ingredient, and the best warm-tone papers (such as Forte Polywarmtone) were never the same again. In some ways, those who bemoan the passing of the ‘good old days’ are, for once, right."
On modern Warm tone papers . . . . . . .and certainly inferior to the Holy Grail of the old formula Cadmium ridden and highly environmentally friendly Agfa Record Rapid. . . . Ridden means on the back of or rather the paper was dependent on it's Cadmium content
I looked at some European warm tone Chloro-bromide emulsion formulae I have and and the Cadmium halide level varies from about 2% up to 6.5% of the total halides by weight, and is always added at the precipitation stage.
B&W Warm tone paper - From a 1969 Japanese Patent:
(A) solution (65° C.) Water 300 ml. Gelatine 10 g. Sodium chloride 9 g. Potassium bromide 8.7 g. Cadmium chloride 0.5 g. Citric acid 0.2 g. (B) solution (about 60° C.) Silver nitrate 25.0 g. Water 250 ml. (C) Gelatin . . . . . . . . . .
Approx 3% by weight of halides is a particularly significant level of Cadmium.
The major impact of the Cadmium removal is that the potential image colours are reduced. The newer papers are still excellent they just haven't the flexibility, but there are ways around this.
I've never looked into why the Cadmium's required but it's doesn't seem to be needed in slow speed chloro-bromide papers designed for Contact printing but it was used in projection speed Chloro-bromide enlarging papers.