Michael Swan refers to the whom-clause as "not generally considered correct." In his book, he mentions an example for a 'whom-clause' :
This is a letter from my father, whom we hope will be out of hospital soon.
He says the above sentence will be "more correct" with who in place of whom.
My questions
Is the the sentence with whom still correct?
I always thought that whom is used in relation to an object rather than a subject, as in:
She is the woman whom you met at my wedding last year.
Restrictiveness aside, I see no difference between Swan's sentence and the above example. Am I missing something here?