So the mentality in the game is not to get a DF group for Titan, but to premake one (usually from people in Mor Dhona). This makes sense, especially since the DF gives you two tanks when you could take another dps (or healer if you ascribe to the 3 healer strat). Obviously, if you can go with FC people that is better, but my FC isn't geared enough yet. I have been trying for a few weeks now to down Titan with premade groups. I have had varying levels of success, but pretty much they always devolved into me standing there tanking Titan while watching people get blown up by Titan's AOEs.
Last night, after taking a break for 4 days or so from attempting Titan since I felt like I was banging my head against a wall, I decided to try again. I got a group together in Mor Dhona and I felt good about the group since they were all talkative and had multiple darklight pieces of gear. We proceeded to try about 5 attempts against him and only made it to about 40% health on our best attempt. Even worse, we had a bard that was standing on the edge of the arena when the healer kept asking him to stand closer to everyone else for AOE heals during tumults. He was probably asked 10 times to move closer but he never did. After we decided to call it quits, he said that he didn't know what the problem was, but he knew he was a good player and in the right anyway.
There was only an hour until maintenance at this point, so I was thinking of just logging. Then, I decided to just use the DF to find a group because, well, it couldn't be that much worse. As a tank, I only waited about 5 minutes. The first attempt with this group we got him down to about 15% and wiped because one of our healers messed up and died. On the second attempt, we beat him with only one bard dying about half way through.
Side note: the only really annoying part was the other Paladin pulled threat off me once and was on my heels threat wise the entire time because he just spammed his Rage combo over and over. I would have volunteered to dps the second attempt because of this since I know how to manage my threat when dpsing by using riot blade for a while until the other tank is way ahead, but I had 600 more hp so...
Anyway, after 3 weeks of trying I finally finished Titan HM with a DF group. I know I may have gotten extraordinarily lucky with the group members I got, but if you are fed up with bad premade groups, try the DF a few times and see where that gets you.