Barnbaum uses 320TXP sheet film. Almost irrespective of developer, that film is (by design -- it's intended for studio portraits) all toe. Its characteristic curve almost never stops rising. Thus, even though my testing yields a classic 0.1 over film base + fog EI of 500 in XTOL 1+1.5, I expose it at EI 250. This gets everything up off the flattest part of the toe and results in a tonal scale close to other film/developer combinations, but with more "highlight sparkle." I still place scene elements the conventional way, e.g. shadows on III, but relative to EI 250.
Other film/developer combinations with short toes and long straight line curve sections can be used at their 0.1 density Exposure Indices while still "placing the shadows on III." Barnbaum's approach applies only to the way Barnbaum works, i.e. the film he uses. If his method is employed when photographing with a film/devloper combination that has a long shoulder, bad things can result. Beware of dogma.