Class balance based on PTR Testing
The PTR does not exist solely for balance feedback. They provide crash reports, bug reports, having the patches simply live on a test environment with people actively playing helps us catch a great number of issues that no one would even need post about. Beyond that though the bug reports that are posted are extremely helpful, and overall the PTRs lead without a doubt to a more stable patch than it would have been were there no public test.
In direct answer to what you're referring, unless there's new content, the number of people on the PTR is really pretty low. Too low to pull reliable metrics to base balance changes on. Unless there's new content to drive people to the PTR there generally just isn't a sample size. Which is fine, because we can make changes after the PTR once the patch hits the live realms. Issuing hotfixes after a patch is by no means something new. We've used hotfixes for quite a long time, but since Cataclysm and the new community site, hotfix changes are front page news through the blogs. Which is awesome. Before we were throwing out pretty much the same amount of hotfixes we were after 4.0.6. Difference being we didn't have a great way to tell anyone about them. So now hotfixes are very visible and it makes it seem like we're going crazy with them, when really it's just increased transparency into the changes we're making.
Going back to your question, the PTR does many great things for the patches, and it should be expected that we're not going to make balance changes based on forum posts alone. The designers don't believe their own play experience is reason enough to make balance changes, although it can be one part of the puzzle, and the same goes for us reading about yours. (
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