[achileas]

>If it's another physical action within known physical laws, then nothing interesting is happening and it's a failure of the experimental setup

I'm not sure what makes you think this. There's no failure in science when an effect is observed and it's explainable within the frame of current theory. If that was the case every experiment I've done would have been a 'failure.'

[mikeash]

With the experiments that showed a result, that result is not explainable within the frame of current theory. The whole purpose of the experimental setup is to isolate the test article from any possible interactions that could exert force on it, other than the one being tested. If the results seen so far are due to mundane interactions, then that isolation didn't work. Is that not a failure of the experimental setup?

[achileas]

IIRC, the recent tests are to reduce experimental error, not 'mundane interactions.' Just because there may be a way to explain it within the frame of current theory that the original researchers did not pursue or understand, still doesn't mean the experiment failed.