Mastering Piano Technique: A Guide for Students, Teachers and Performers

Are the techniques taught in this approach well regarded by piano pedagogues?

Haven't read it, don't know his approaches in any detail but know some from discussions here (never heard of him before that). From what I know, his basic concepts are very sound and interesting, and I think they are indeed well regarded by at least most pedagogues. As is the case with almost any approach, some of his details are criticized but I think most of them are widely felt to be reasonable.

BTW it might help you get more replies if you yourself say more about it, including what made you ask.

I've been in one of his workshops - it's all quite sound.

i bought this book several years ago when i was a beginner. it is a good book focusing on physical aspects of playing techniques, which is helpful to me especially when i had no teacher and tried to figure out myself the best ways to play without hurting myself then.