cir·cum·spect   [sur-kuhm-spekt] Show IPA
adjective
1.
watchful and discreet; cautious; prudent: circumspect behavior.
2.
well-considered: circumspect ambition. [taken from
www.dictionary.com]
According to definition 1, 'circumspect' means cautious or prudent. Manlybannisters was being cautious in avoiding agreeing with the proposition that even a small minority of females can have pubic triangles whose tops reach the bellybutton.
You are misinterpreting that definition to suit your misuse. 'Circumspect' comes from the Latin meaning to look around, consider all options - we use it in the sense of cautious only in the context of cautious not to take unconsidered decisions.
Here are some slightly better (more explicit) definitions:
Definition of CIRCUMSPECT
: careful to consider all circumstances and possible consequences : prudent
circumspect (comparative more circumspect, superlative most circumspect)
Carefully aware of all circumstances; considerate of all that is pertinent.
http://en.wiktionary.org/wiki/circumspect
The adverbial form and its definition may also help you understand why your use of the word is incorrect:
Adverb
circumspectly (comparative more circumspectly, superlative most circumspectly)
In a circumspect manner. With consideration for all that is pertinent.
http://en.wiktionary.org/wiki/circumspectly
Your incorrect use of vocabulary aside, saying I'm 'cautious in avoiding agreeing' with something is just about the stupidest thing I have read recently - I'm not cautious to avoid agreeing - I outright disagree! I have seen no evidence of the thing you claim to have seen. I have seen no photographic evidence either. This morning I went looking to see if I could find even a picture of a woman with pubic hair going all the way up to her belly button. I can't. I find only pictures that agree with my real life experience. A treasure trail is about the hairiest you can hope for - and even then, on investigation, most of those women were either tucked lady-boys or post-op MtoF transsexuals.
That's the thing about pubic hair, it grows on the PUBIS.
Even on very hairy men the hair on their stomachs is different to the hair on their pubis. I didn't even find an image of a man with a pubic hair triangle where the top line was on level with his belly button.
Please - anyone - if you have such pictures post a link here. I will happily defer to authentic, photographic evidence of a woman the top of whose pubic triangle is at, or less than an inch under, her bellybutton. I'd be quite surprised to see a man with pubic hair up to his waist, too.