I had to do that after I got put in a group where there was no way to view the description or episode list without also starting to play the selection (in browser). On a console app the other day it would start playing an audio preview of anything selected making scrolling through my options extremely annoying. I quit the app almost immediately. I don't mind being in the testing group but I would definitely like the option to quit a test group. Wouldn't that feedback be valuable to them?
The feedback is generally implicit in that if it causes problems for a lot of people then the test fails because you stop watching Netflix with that device.
That being said, if you call in to customer service they can remove you from the test if it turns out that's actually the problem (sometimes the problem is that you are in two conflicting tests for example) and they do mark that down as feedback. But they want you to call in so they can better understand and record the failure mode.
You don't even have to call, you can do it via chat, if you're not the kind of person who like to talk on a phone. :)
