It seems that blizzard started off during the PTR atm with the introduction of cross realm heirlooms for it to be included in WoD. Followed by that, they're trying to test the raid browser so they can make sure to know how to improve it in WoD. So my question is, is WoD's features currently being tested incrementally so that blizzard could minimize the beta let's say to 1-2 months for a faster release? And would you like the new expansion's features being tested not on the beta but instead in updates on the PTR?

I didn't find the right solution from the Internet.

References:
http://www.mmo-champion.com/threads/1402877-Is-the-alpha-beta-for-WoD-being-technically-tested-right-now-(via-PTR)

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