Though he is said to have written 42 essays, only 7 fragments of Shenzi's work have survived. The greatest part of these, on 6 bamboo strips from the Warring States Period, are inaccessible to the non-Chinese speaker. A treatment of these fragments is to be found in one doctrinal thesis (The Shen Dao Fragments; Paul Thompson) but is only available at an extravagant price. What remains for this author, therefore, is what we have in the Tianxia (33rd) chapter of the Zhuangzi. This chapter critiques many of the philosophers of the Warring States Period, including Shenzi.
The author of this chapter clearly seems (to me) to have been a syncretist of decidedly Confucian persuasion. A.C. Graham includes it in his Syncretist School of chapters. Liu Xiaogan, who also sees this and other chapters as syncretist but prefers a more contemporaneous designation, includes it in his Huang-Lao School (Chapters 11B-16, 33). He believes this school of thought to have been part of a larger Zhuangzi School, but to have significantly diverged from him in its efforts to integrate Confucianism and Legalism with 'Daoism'. Daoism, as we currently think of it, he goes on to say, has its beginnings in Huang-Lao. I would add that his other two divisions of the School of Zhuangzi, the Transmitter School (those closest to Zhuangzi's thought) (Chapters 17-27, 32) and the Anarchist School (those most removed from his thought) (Chapters 8-11A, 28, 29, 31) also diverge toward what became religious Daoism. [The 30th Chapter, "Discoursing on Swords", is considered by nearly all scholars to be completely spurious and unworthy of inclusion in the Zhuangzi.]
My reading of the Tianxia chapter sees the author as more Confucian than Daoist; he does not even presume to critique Confucianism, but rather suggests it as the true, all-encompassing dao by which to critique all the others, including the proto-Daoists Shenzi and Zhuangzi. All other philosophies are the product of "nook and cranny scholars" who got some of the true dao, but not all. His analysis of Shenzi's thought is thus necessarily skewed.
This is not to say, however, that he does not appreciate many aspects of Shenzi's dao. In fact, what he does affirm in Shenzi, and indeed most all the other daos he critiques (Huizi and his fellow rhetoricians are alone in being unaffirmable), would probably make a true Confucian squirm. His Confucianism is in fact syncretistic and unorthodox.
The next post should hopefully begin to actually examine what Tianxia had to say about Shenzi.
You can check out Scott's writings on Zhuangzi here.