TA-5065. Fix gruff with repeated yaxis

@davywentworth

![screen shot 2014-03-09 at 1 19 36 pm](https://f.cloud.github.com/assets/1187096/2368995/386a69ee-a7c8-11e3-954a-4bff2b981258.png)
![screen shot 2014-03-09 at 1 19 42 pm](https://f.cloud.github.com/assets/1187096/2368996/3877dfac-a7c8-11e3-9900-167f755e69d2.png)
![screen shot 2014-03-09 at 1 19 49 pm](https://f.cloud.github.com/assets/1187096/2368997/387fd5ae-a7c8-11e3-9260-f6ac49363f9d.png)
![screen shot 2014-03-09 at 1 19 28 pm](https://f.cloud.github.com/assets/1187096/2368998/3b4f9a62-a7c8-11e3-99d6-432af1c53a6d.png)
![screen shot 2014-03-09 at 1 19 59 pm](https://f.cloud.github.com/assets/1187096/2368999/3b5191c8-a7c8-11e3-836e-8ce74e5d996f.png)