[ Les - Can you remember more about that photographer that had streaking problems caused by presoaking.
The photographer was a lady called Fay Godwin and the problem was streaking in even toned areas such as skies. At on point she had a sizeable number of undeveloped films that she would not process until the problem had been sorted. The final analysis was the the pre soak water was removing something when it was poured away so Fay went through the labourious process of pouring the pre soak water into a graduate containing the undiluted developer and refilling the tank with it. The main thing was that it eliminated the problem.
Ed mentioned a similar problem with Agfa, I can verify that for John Davies another British photographer told me that he used Agfa 100 and had the same problem for a while and solved it in the same way as Fay.
It was about 15 years ago that this happened .