Articles on the "Logic Puzzle":
Jeffrey Birnbaum from the Washington Post discusses the issue, including
On a single day last week, of the 8,262 times the logic puzzle was viewed in the House, only 1,568 people answered it and moved on to send a message -- a 19 percent success rate. It's unknowable whether this means that computers could not crack the code or whether actual humans were frustrated and gave up (though there were probably a combination of both).
There is also a Roll Call article on the issue.