lucy24 - 8:55 pm on May 16, 2013 (gmt 0)
I have referer traps, I just do not find them the most common reason for trapping.
In my test site's logs I find ###loads of blocked requests with .ru and similar referers. But the referer blocks are only in place on my main site; on the test site these requests are getting blocked further along the line by IP. Belt and suspenders. If I disable mod_authz,* the referer test will get them.
* This is why people have test sites. I put in an "Allow from all" line to check something, and forgot to remove it until two days later. Ugh. Fortunately there are not many robots who modify their behavior dynamically based on response.