When he talks about using this dangerous knowledge to sail away from morality, he means morality is just fetters on humans. Psychology, sociology, anthropology, humanities, etc can show us which beliefs/behaviors are fetters. This is dangerous in the sense that it unfetters your neighbor, placing him out of your control and predictive prowess. You don't want anyone to know how to remove these fetters so even their gained perception of these fetters is dangerous. Your gained perception is dangerous for others as well which results in their emotion toward you, who is their now-unknown. You can see examples of this by just looking for one-group's hatred towards another-group's worldview.
However, just because you've unfettered the psychological self through the work of gained perception, does not necessarily mean you've unfettered your physical self. So with your head down you will skulk back to put those fetters back on, at least to make it look like you're fettered to others.