Yours is an anecdotal experience, same as the OP. It's not enough to warrant representation of all population. If Jiro is korean, does he represent all koreans? Hell no, he is one lazy korean. 
There are a bunch of tangents that are being discussed in this thread, and frankly they need to be split up by what we're discussing them by.
Examples:
Grammar structure, spelling/alphabetical replication of the word, word awareness/concept/usage, phoneme awareness.
I've read peer-to-peer reviews of this subject.. because it's an interesting subject. basically implications in the discussion sections for many of them come out tantamount to something like this, GENERALLY speaking.. not on an individual case by case basis:
Deaf (profoundly): best concept of word usage, bad in phonemic understanding, good in spelling, grammar is a touchy subject and often there are discussions to why their grammar is not "the best".
Hearing: worst in spelling, worst in word recognition, but best in phoneme awareness (obviously).
Hard of hearing, with enough hearing to retain normal communication with Hearing folks: overall well rounded, performs better than deaf in some and better than hearing in other concepts.
If you still have access to search database articles, I would highly recommend something like that other than just throwing things around in loops arguing semantics.
