Of note here is the work of Linner, et al (J. Histochemical Cytochemistry, volume 34, page 1123,1986) who used ultra-high vacuum systems to process tissue. Tissue water is first vitrified, after which a vacuum is used to remove the "immobilized" water (at lower temperatures than freeze-drying); no fixative or chemical dehydrant contacts the tissue. The result is that their electron microscopic images are quite different from conventional electron micrographs. It seems intuitively clear that orthodox fixation, dehydration, and embedding remove and/or alter many subcellular components. In contemporary cell science, we need to be concerned about what has been lost by standard methodology.
Perhaps Dr. Hillman could have been more politically astute, but it appears he is correct on this issue. If he were indeed forced into early retirement merely because of an ability to alienate peers, science once again found a stupid way to deprive itself of a scientific mind ...