Iala
and so do the Kami, who very actively persecute anyone trying to gain knowledge about the goo, sap, and indeed the Dragon (the existence of whom they want to hide, therefore any research into the Dragon has to be suppressed as it would inevitably lead to knowledge that the Dragon indeed does exist).
To destroy a thing, you have to have knowledge of that thing.
Could you point me toward any objective evidence to substantiate your claims, as in, claims made by the Kami about themselves or information presented in Chronicles as fact and not accusations? I would be very interested in reading that material. Remember, this is an OOC forum, by necessity, so please keep that in mind.
Iala
The Karavan do not prohibit studying the Prime Roots, though they do discourage digging deep (but literally!) as doing so may disturb the Dragon and bring about his awakening.
You are correct here, Prime Roots isn't completely off-limits, so I was indeed mistaken: "The homins are forbidden to descend underground in quest of the dragon's lair for fear of stirring its wrath." It is only forbidden, apparently, to search for their dragon. I don't know what the writings at the temples say, as I have no Karavan-aligned characters.