Hi, Rusty!
"knee -high to a grasshopper" isn't in MY Brewers! What does it say about the saying in yours?
I've found the bit about Kit's Coty House though. I'd never heard of it before you mentioned it, let alone been there! nor, I am afraid, do I know of Katigern and Vortimer - had you heard of them before finding this reference in Brewers?
I have been to Maidstone though! it's the County town of Kent and quite an attractive town with a river running through the town centre.
White cats are often deaf. I shall have to look this up, but I think it's something to do with a pleiotropic gene - having a pure white coat and blue eyes and deafness. But not all white haired cats with blue eyes are deaf.
Presumably hence the saying "as deaf as a white cat" although I have never ever heard it said .
" as deaf as a doorpost" is the idiom I know?
I wonder if Jazzgirl will still be standing by the roadside waving her placard if she is over at her friend's house?