How to verify that lines were only moved, not edited?

I thought there was a way to use git-blame to find out whether a change only shuffled lines, but otherwise did not modify them. I tried "git blame -M -- the/file", but it does not work as expected, neither with a toy file nor with a 5000+ lines file (with 55 lines moved).

git init echo A > foo echo B >> foo git add foo git commit -m initial echo B > foo echo A >> foo git commit -a -m swapped

The results are: $ git blame -M -s -- foo ^e3abca2 1) B 6189cb46 2) A

I would have expected: ^e3abca2 1) B ^e3abca2 2) A

Oh, look! This produces the expected result: $ git blame -M1 -s -- foo

while this produces the same as with just -M: $ git blame -M2 -s -- foo

But neither helps with my 5000+ lines file. Does it mean that the lines were changed? But I'm sure they were just moved! Please help!

-- Hannes