Daelo, one of Blizzard's designated Blue posters, recently came onto the boards to acknowledge some issues that will be addressed in future patches and updates to the Mount Hyjal Battle in the caverns of time.

To recap Daelo's points, here's a quick primer. First off, They're planning on extending the leash of Archimonde to make the fight more manageable, but not so easy as to allow everyone to use the Well of Eternity.

Second, they've weakened Thrall and Jaina throughout the different battles, lessening the overall hit points and damage of the two. This is to ensure that a raid can kill a boss or fail without the NPCs accidentally stealing the kill from the raiders, allowing the raid team to redo the encounter so they can grab the loot they were aiming for or continue the battle with the NPCs (if they're fast enough). A strong fix is planned for the future, but this short-term fix they've implemented should suffice in the meantime.

Lastly, a future patch will reduce the number of waves before each boss. Instead of 12 waves prior to a boss, Blizzard will make you go through 8. They're also making it a little friendlier for raid groups by lessening the number of creatures that pop up in each wave, as well as introducing epic drops for added rewards.

In any case, you can find Daelo's note to the raiding public at the read link below. Enjoy!