This book's front cover seemed somewhat familiar... since I do make use of... and LOVE using my BTZS developing tubes... so much easier than tray development... so much less of a 'hassle' than my pile of Kodak film hangers and half-gallon tanks... and so I hustled to the bookshelves 'down there' for a search and rescue....
I am somewhat sure I purchased that book when I was first 'persuaded' to 'try' the BTZS tubes, but it seems I may have either lent it out... and it has (either) not been returned... or is still packed in an unopened box from when we 'moved house' when 'the kids' moved out.... so... when I can find some spare 'enthusiasm' for more box-hunting/ searching... I'll take another look.
I did, however, 're-find' a book (in one of the 'unsealed' boxes) "The Edge of Darkness" by the late Barry Thornton that 'piqued my interest' a significant number of years ago (15 ???) that might just prove to be an interesting re-read.
Ken