A Genuine Blow (Sic)

"Your invitation to Reverend Rick Warren to deliver the invocation at your inauguration is a genuine blow to LGBT Americans."

- Joe Solomnese, the president of the Human Rights Campaign, in a letter to President-elect Obama

My question: When quoting someone else, would it be appropriate to add "(sic)" to indicate a pun or double-entendre that is so incredibly obvious, you want to clearly disclaim responsibility for it? Or is "sic" only for spelling and grammatical errors and like that?