iRule to select test pool based on cookie/env variable?

Thanks for all the feedback - I am testing the member=[1,2] iRule - (the tester's IP varies) - it seems to work great - EXCEPT

 

I am having problems with the test node receiving traffic despite being in a lower priority group (1) than the prod node (2).

 

 

Why would this be?

 

 

Is there a better way to ensure the test node member never receives traffic unless ?member=2 is specified?

 

 

thanks