Weird that this was not spotted in Lamannia.
There must be a different mindset over there on how to play. I've never been over there so cannot say.
But I could imagine that people group up to see the new content and get phat lewt. Perhaps never running old content. It must be difficult to motivate players to test old content which they know well. In Maj's defence he did ask people to play on Lamannia as the would play on live. But as he said, no excuses, and in the end the fingers can only be pointed at Turbine and not the players.
Regarding testing, which can quickly spiral out of control with the infinite number of options.
Perhaps a few quests could be picked for soloers who attempt to minimize their kills to test dungeons to verify that it's still possible. Or to make a note of before and after behaviour or even comparing a FRAPs capture between before and after.
Or I guess you could summarize it as playstyle testing, solo with a rogue, solo with a caster, solo with a x etc.
Guess Maj can chalk this up as a learning experience - he learns something new with every patch!! Hah