Revert "Revert "Discussion repeat fix""

Reverts guardian/frontend#4949

After reverting, errors have now gone up

![screen shot 2014-07-02 at 13 07 59](https://cloud.githubusercontent.com/assets/74132/3455467/9024e5ce-01e1-11e4-8f45-ed3f426e1331.png)

Which is odd. Why wasn't it this high before the 9.50 release?

cc: @jamesgorrie