I wasn't even done sputtering yet when CM Takralus pretty much said what I would have, were I not busy sputtering.
Even with beta tests, bugs get through. Anyone remember Sinestra? At the time Paragon killed her, they talked about the fight and its issues. One of those issues was that Paragon was one of the first guilds to really see Sinestra, and as a result, the fight had bugs that were not discovered until after Paragon began seriously pushing for the kill. In other words, not testing Sinestra on the PTR had consequences that may be acceptable with a single fight that only a few players will even see while it is current and that will be fixed by the time other guilds go back while outgearing it.
These consequences would absolutely be ruinous if they were felt by everyone attempting to do normal-mode raiding content. To a degree, not running a PTR or beta test is irresponsible on Blizzard's part, especially with content meant for the majority of players. I really think the responsibility for walking into a raid fresh, unspoiled by tips or beta testers, is on the players. Better we have some spoilers than untested content.
And yes, we had both an alpha and a beta for World of Warcraft. They didn't translate to having everyone know everything when it went live. Heck, half the time, it just confused you because stuff changed so much. I really fall on the side of those who appreciate beta testing.
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