In all fairness, every interview host wants her to karate chop him or her. They will say anything just to get a rise out of her. And it's not fair to lay the blame of Eric for giving in to them on that one. Of course when she appears there should be chopping...everyone expects it.
However...I agree, it is over used and she does over-react...but I really don't think she has much of a choice over it. She did very well on the Late, Late Show with Craige F when she resisted the chop, resisted the chop, resisted the chop, only to chop him anyway. That was funny, cute, and her final chop was unexpected.
The chop has always been about being "unexpected" but now it's expected. A muppet movie in which she doesn't get a fight is like having a Muppet movie without original muppet songs (Hint: MFS *cough*) But sometimes they do feel very thrown in there (Hint: VMC.)
I feel that her recent appearences have been slightly bland, and ever so slightly annoying...but, she has struck some comedy gold in there. Example: In one of the UK interviews she literally walked off camera and insisted she continue the interview from there. Also on Loose Women, she did not get cross. She smoothed things over and they all asked her advice and she was treated like a real star.
Many of the people doing the interview treat her a gimmick, a one-line joke, etc...Loose Women and Craig F treated her as a star and she rose to the occasion and made memorable appearences.