Although I had never heard of alkaline stop baths -- the very idea seems oxymoronic -- I assume that these are the sort of buffer baths used for interrupted development of. e.g. aerial cine film and litho films.
I also don't see a reason why alkaline stop bath is necessary, or preferred, with pictorial continuous tone processing of modern emulsions. The story may be different with classic lith development as well as other high contrast applications where development time must be very tightly controlled, or individually determined by inspection, etc. But with the sort of processing we do here, a fraction of a degree of temperature error can cause bigger error than slow stop using water rinse or acid stop bath.
Although Troop said a lot of good things about all alkaline processing in his book, I see no reason to do so with modern materials.
The 'all alkaline' route has merit with staining developers such as Sandy's approach, though as he says, density loss with weakly acid baths is rarely significant, but I'd be suspicious of Peter Hogan's assertions that all-alkaline processing is invariably superior and that acid stop baths are merely a matter of convenience. As every authority on the subject, and every manufacturer, describes and produces acid stop baths, and as immense amounts of research have been done both by major companies and by enthusiasts on this, I can't help feeling that if alkaline stop baths and fixers were actually superior, that's what they'd sell.
I agree with your first sentence. There are all sorts of wild claims made in the description of alkaline stop bath and alkaline fixer. Frankly, if there were a way to make some of those claims to be scientifically truthful, I would definitely do that. In reality, I've been making my emulsions and processing chemicals for several years now, with continuous effort to update the scientific knowledge and practical formulation, but I must say some authors and marketers are writing hopes and hypes not so much of truth.
About the second sentence, I currently do not license any acid stop or acid fixer formula, although I have them in my private formula book. Although I see some advantages with my alkaline fix, the real reason is that there are already enough acid stop baths and acid fixers cheaply available on the market. Regarding what sells, I think if one has a bit of intact brain and wants to make money, photographic chemical is a wrong place. That said, if you want to make money by selling fixers, I think the best way is to make generic acid fixers (perhaps in a few different colors, scents and flavors) and sell them at a buck cheaper than competitors. (Sad reality, though.)
As I say, the rules with some staining developers -- maybe all, I don't know -- are different but I thought the above formulae (from Haist, as ever) might be of interest.
Which formula is from Haist? I thought those from US Pat 3284199, Maffet and Peters, 1963, assigned to Du Pont de Nemours, not Haist... or am I missing something here?
