I'd agree with the general consensus of posters regarding the trails present difficulty rating.
For those who may not know this though, it should be understood that that work was done so as to access and maintain the natural gas pipeline which runs up and across Amasa Back and provides that service to the Potash Plant across the gooseneck bend of the Colorado River. That has been there even before the trail was re-named to "Cliffhanger" IIRC.
Most of the trails which we currently use were at one time in 'subaru' state when first constructed. It is merely due to their age, the fact that they are no longer needed or used by those who *first constructed* them, natural erosion, and very heavy use by our means activity that they've gotten to their general present state of 'disrepair'/challenge.
Given time (probably in very short order), all will return to their previous known state of difficulty.
As a sidebar here, a similar, though not nearly as drastic action took place on Moab Rim trail about 4 or 5 years ago. We had to run that trail in the dead of winter with snow on it to check it out prior to posting the status of this trails rating in the then upcoming RR4W Easter Jeep Safari. Some rock fill had been placed here and there so that a more modest (far more modest) rig could do the trail. Our assessment was that due to the general consistent steepness of the trail and the time between the work done/our viewing it, and the months before Jeep Safari, there was no need to modify the rating or remove the fill. Additionally, in that instance, the fill was not necessarily done at the exact trail alignment (rightly or wrongly depending on one's viewpoint). Before long, all had returned to normal by natural weathering and action.
I'd also add that many trails were 'unpopular' years and years ago, and were relatively benign and easy when they had their original names. When new names were given, popularity soared, as did everything else.
e.g. :
Flat Pass = Steelbender
Arths Rim = Metal Masher
Amasa Back trail = Cliffhanger
Capt. Picky
