Re: Yanking wrong text

[Richard Stallman]

      That's because the selected region happens to be the same as the
    first region added to the top of the kill ring, and due to optimization
    C-y inserts the second element of the kill ring.

    You may ask why do I want to replace a region with exactly same text.
    Usually text is very large, so I don't see that these regions have
    no differences.  My goal is to copy the region to another place regardless
    of the fact that it happens to be the same as the selected region to be
    replaced in another place.

This heuristic avoids annoying results in a common case.
I wonder if we can tune it to detect that common case
while not triggering in your case.