I read it as an idiom to express surprise[0], not literal disbelief. [0] http://www.phrasemix.com/phrases/i-cant-believe-someone-would-do-something http://www.

I read it as an idiom to express surprise[0], not literal disbelief. [0] http://www.phrasemix.com/phrases/i-cant-believe-someone-would-do-something http://www.phrasemix.com/phrases/i-cant-believe-someone-woul...