I've read two of them. Moderately interesting. Some out and out bad advice here and there. Cook pork to 170 for example in I'm Just Here for the Food.
I wouldn't own any of the ones I've read. Now yes, I'll cook pork shoulder beyond that temp, but most people aren't cooking pork shoulder. 170 will ruin most cuts of pork.
His techniques are more extreme than they are worth in my opinion (Hoisting huge clay pots into 500 degree ovens for cooking bread). Yes it works and produces good bread but it isn't practical for most home cooks. I think there are other techniques to produce good bread more suited to home cooks.
Try your library and see for yourself. Then you can judge their worth to you.
Phil |