"This was a post more in response to text from 01-11-11"
Which doesn't answer the question of how resonant frequency relates to sibilance.
It also does not refute the idea of buying the cart one wants and seeing if one can make it work.
And you failed to put quotes around my remark:
"That is one way to do it. The other is to buy the cartridge you want and if it does not work ask for help. If it cannot be made to work then one must go back to the previous cart, buy something else, or replace the arm. In this case I really wanted a Delos or a Kleos. "
Robert