Well, it's not that Fracture is bad to use period but it needs to be used at very specific times.
If you do your normal rotation and you reapply Touch of Death, if you use Fracture as well during that rotation, you will miss one GCD of Dragon Kick and Twin Snakes, as said before(Unless you skip Bootshine and True Strike but that's a huge dps loss as well). It also costs 80 TP. It's situational.
I guess that rotation isn't a gigantic DPS loss though, mostly it's extremely TP-inefficient but maybe a 6-8% loss?
