I don't think we cover it in depth there and I'm perfectly willing to take this thread on any and all related sidebar's...after all its about being kajira which basically in the lifestyle is just another type of slave which some consider to be the next stage after being a submissive in one's journey.
From a Gorean perspective I can say that there is a certain duality at play in all things.
The quote you give is one of many similar such sayings in the books, some like the one mentioned are intended to help educate or inform one on things to be wary of. Goreans aren't very big on complacency lol.
Another such warning goes something like "be wary of la kajira, lest one becomes enthralled instead at her feet".
Again a warning against complacency.
See a kajira isn't necessarily some one who is meek and mild all the time....she is also known in the books for being bold and primal perhaps even dangerous for she is the embodiment of a "she-sleen" (a six legged mammalian hunting animal akin to a tiger on earth in the food chain) not a challenge to be taken lightly.
A she-sleen can't be domesticated fully ... nor in the opinion of a Gorean of Norman's making should she. She can however be "mastered" but one must be strong to do so. To "master" one whom one loves? One must be (at least in her eyes) as the strongest of the strong. Strength of will, of character, of bearing, being the strength to which he is referring.
Being an anti-feminist didn't mean Norman didn't hold women in high regard.
In a way Norman often portrays kajira to be the ultimate embodiment of being a woman, of being someone who is attuned to their nature and comfortable with it. (they don't all start that way...it's a long journey)
http://www.bdsmlibrary.com/forums/showthread.php/17006-Gorean-Philosophies
ohhhhh here is a link to the philosophy discussion...enjoy!