Sorry for not reading past more than your thread PE but it's late and I'm off to bed now. Just to say that history is a strange medium. Mid 70's (1976 iirc?) we had a severe drought in the UK. Hosepipe bans etc. The water shortage was bad enough to be of interest in the photo mags. RC paper best thing since sliced bread and all that.

Anyway, up comes an a letter from Ilford about how to conserve water by using the ever increasing number of inversions then dump routine. This was imo, and I'm pretty sure to everyone else at the time, a purely stop gap measure to use during a water shortage.

Lo and behold, in the fullness of time it becomes an archival method. Where did that come from? I was buying loads of photography mags at the time, trying to soak up knowledge like a sponge and I had never heard of it before that drought.