RichThesaurus
knock me over with a feather
vs
you don't say
knock me over with a feather
you don't say
intj
Really?; no kidding!; is that so? (sometimes used sarcastically in response to the obvious)
How often have the words
knock me over with a feather
and
you don't say
occurred in a corpus of books?
(source:
Google Ngram Viewer
)