I have Barbaum's book and I know the shot you are reffering to Aggie. But that is totally different.

One of the reasons I like the BTZS better is that you start by defining the range your PAPER can accomodate and then you make a family of curves with film to adjust the developing to fit that range. So, for example if I have a situation where I have a 13 stop range I would lower the exposure index of the film from 400 to 200 and then develop for very little time. I am pretty sure this was Barbaum's situation, the woman is sitting against a pillar in full daylight and he is inside the cathedral looking out to her, so his brightness range is very high, but I doubt he went into reciprocity failure as the exposure would have been too long and the woman's movement would have been apparent. So he simply applied development controls for a high contrast situation.

What Ta describes, if I understand correctly is that his teacher grabbed a published H&D curve and somehow was able to determine that he needed a 30 min exposure to take into account reciprocity failure from looking at this curve. IMO this guy is either a genious and he needs to write a book on sensitometry (which I doubt very much), or he is trying to show off and is actually giving out wrong information.