You don't need a very big group to get this one done any longer, if that's any help.
But this was my problem as well, always playing catch-up.. I had already visited ToT in the LFR quite a lot before even getting to the CoC quest. So after that it was like... 'wait, now I have to go BACK a shitload more times? And then AGAIN for the titan runestones?" 9 wings or so of ToT since then have yielded 7 secrets.
Uncle