Monobaths are best for applied uses as there is little need for tight temperature & time control, between about 15ºC-27ºC. They have been used for military & space applications, as well as Polaroid, Xray films, Microfilms etc.
I worked on them so that potentially with a given emulsion the only user variable was exposure, and the monobath took away the parameter of under or over development over a manageable temperature range (15ºC-27ºC).
Geoffrey Crawley's FX6a monobath works well and can be fine tuned to match specific films. L F A Mason in Photographic Processing Chemistry lists a typical Monobath formula. Mason was head of Research at Ilford, his editor was G I P Levenson who held a similar position at Kodak Ltd (UK).
Typical Monobath
Sodium Sulphite (anhyd) 50g
Hydroquinone 15g
Phenidone 10g
Potash Alum 18g
Sodium Hydroxide 18g
Sodium Thiosulphate (5H20) 210g
Water to 1 litre
Water must be softened or deionised/distilled to prevent precipitates.
Use 1+1, 600ml working solution will process 6 rolls of 35mm/120 film, minimum Development time 7½ mins between 15.5ºC/60ºF and 26.5ºC/80ºF
I've not tried this particular monobath but suspect it's similar to Ilford's Monophen which they sold commercially.
Ian