http://www.springerlink.com/content/r016375q664464x7/fulltext.pdf
One of the things they tested on HUMANS not just mice, was salycic acid. It was shown to increase human sebum (near the very end of the article). Also topical corticosteroids reduced human sebum.
Many surficants increased sebocytes in the study. The authors pointed out that this might not necessarily happen in humans because mouse skin is so much more permeable, but the results of the sodium laureth sulfates were a little suprising. For the life of me…lets say selenium sulfide -does- penetrate to follicle depth and inhibits prostaglandin b-2 for instance, which is supposed to be beneficial, but also increases sebum production and the amount of sebocytes…might then its negatives almost equal its positives?
Do you have any observations on this stuff?