The following will be a concept to implement an easy mode for raids without most of the drawbacks.
It seems to me that raids could really use an extra, easier, difficulty setting besides normal and heroic. There are a lot of people that feel the difficulty of even normal raids is above their capabilities and being able to play on a lower difficulty seems like a fair request. Having more difficulty settings can improve the quality of the experience for all players as it will, for example, mean that people playing on normal will have less of a reason to complain for bosses being too hard because they would have the option of doing the easy modes. Therefore they could enjoy the content the way they like it and not affect the people who enjoy the normal mode difficulty.
Of course there are some problems with this. A lot of other people argue that raid content should not be accessible to you just because you feel entitled to see it and I agree with that. I would add to that, that the epic feeling and prestige of the raid would diminish. The Lich King encounter is a perfect example of this. Heroic Lich King was one of the most epic and challenging encounters ever designed yet most people see him as a total pushover. The reason for this is that on normal difficulty he was really easy which diminished the overall epic feeling of the raid and the character.
Concept
In one of the capital cities goblins and gnomes have constructed a kind of virtual reality simulator. They have gathered information on enemy strongholds and bosses to help heroes prepare for the battles ahead.
The idea is that trough this room you have access to a “training” (easy) mode of every raid. All the bosses in here will of course be much easier than their normal counterparts. You could have the option of talking to the boss at the start off the fight which makes him talk in the voice of the gnome/goblin at the controls of the machine, explaining the fight to you based on the intelligence they could gather. All of the potential story dialogue between player and bosses will be absent as well as any gear. Although some random blue gear could be awarded at the end for helping “test” the program. If you die you will get no durability loss and resurrect at the beginning of the instance.
Of course more experienced raiders could use this to figure out boss abilities and strategies without having to wipe on the normal raids and pay big repair bills. An in game manual describing a boss and his abilities was mentioned to be planned exactly because having to wipe on a boss just to figure out what he does is not considered to be very fun. Working as a well oiled team to overcome difficult challenges is.
In short this could be an easy mode for people who have a hard time on normal mode and a testing area for raid groups to see the boss mechanics and have some basic practice. And all that while making sure the epic feeling of the normal and heroic raids and bosses remain largely untouched.