Seems very recent. I traveled a couple of times this year (Jan & Mar) and the kind helpful girl at the desk asked if I wanted to check in my cabin baggage. Naturally I accepted after removing my laptop. On the third occasion a week or so back, my case was 11.4kg, the girl was trying to insist I paid £30 to check-in the case. I put on a few items of clothing, and had to put the case back on the scales several times, the last time on the scales it was 10.2kg and she wouldn't give me my boarding pass until it was "Within their maximum allowed cabin baggage weight". I dumped a few bits and pieces and and was finally given my boarding pass, nightmare. A friend told me they are on commission to get the extra £30 from unsuspecting passengers. It's crazy, as soon as I received my boarding pass and was out of sight I took off the extra clothes and put them back in the case which is what most people will do, surely?
edit: Another poster on these forums faced the same dilemma with Monarch on another flight, difference is he's loaded and I'm not, he paid the £30!