What is Human Performance Engineering as it applies to instructional design and training?

[itswagon]

Human Performance Engineering is an idea proposed by the late Thomas
F. Gilbert, Ph.D. author of, "Human Competence - Engineering Worthy
Performance" where he championed practical human performance language
and concepts such that performance challenges may be diagrammed,
schematized, compared, and communicated in a practical and clear
sense. After many personal hours of discussion with Dr. Gilbert, I
believe I expanded the concepts Human Performance Engineering such
that they have served the most complex of challenges with technical
systems, political consulting, organization, and community influence,
and etc.

I'd love to find others who have worked at this foundation level of
human performance for further discussion and to learn.