In Object Oriented Perl, Chapter 5, TheDamian blesses a regular expression made with qr (see perlop).

Now, for those without the book, the question is why does he do that while we know that, as you correctly point out, the return value of qr is already a blessed reference into the Regexp package? Especially since the latter circumstance of its own makes for interesting tricks, as a recent poor attempt of mine shows...