I don't get why people expect to jump straight to the newest and hardest content, there is a progression path clearly outlined by what gear is dropped. It's not so much about the gear in EC/TFB, as it is coordination. If you're struggling with EC HM, you will struggle even more in TFB HM.
This is the thing, my non-core raiding guildies don't expect to just jump straight in. They have already done EV and KP nightmare, as well as EC and TFB story mode. However, they are all faceroll easy these days. My guildies now have full rakata / black hole gear, so they no longer have any need to go back to the old raids.
The problem now is the jump up in difficulty to EC HM, especially now that story mode got nerfed. These people in my guild, and I expect many other guilds, cannot make the massive jump in difficulty. Not only do the mechanics become harder but you have to be able to play your class to the limit, otherwise you fail enrage timers or die. Nowhere else has challenged them in this way and wiping over and over isn't helping them learn.
It is my job as an officer and raid leader to figure out a way to train these people, but I just can't do it. For myself and the other core raiders in my guild, we had EC HM on farm months ago, we've done first boss TFB HM and nearly got second boss HM too. But, for us, we were forced to learn the hard way: we learned EV and KP whilst in greens, moved to hard mode in columi / tionese before the hardmodes got nerfed, did nightmare mode EV and KP in rakata rather than BH. It was a clear learning curve. That doesn't exist for new raiders. New raiders generally already generally have some rakata or blackhole gear from dailies. They usually join raids with people who are already experieced. So, for them, it is soooo much easier to clear the first few raids that they dont need to learn their class well. The first time they have to actually play well is when they do EC HM, but it is simply too hard compared to everything they've done to date.
My choice at the moment in guild is to either only take the best players to EC/TFB HM and thus alienate my other raiders or take less well played raiders and accept the fact that we're gonna wipe all night and waste everybodies time. I'm in a lose/lose position at the moment because there doesn't exist a raid in which to train well-geared-but-under-experieced raiders.