As in, a single block quote may map to multiple versions of the contents Cs (by choosing different markers), and you can check that all versions of these contents may be mapped back to this block quote by choosing different markers (though they of course cannot be mapped uniquely).Because ...
And the answer is "no," though perhaps some changes to the spec could clarify this. You can get the first line >1. > asdf by adding a block quote marker to the beginning of the line, but you can't get the second line, because a block quote marker is either a>that is NOT follow...