A thought provoking thread! However, a few misconceptions about RIS. Terrain clearance remains the responsibility of the aircrew under both RIS and RAS. Furthermore under a RIS you can be cleared to a height/altitude below the radar vector chart, under a RAS you can't. I've never managed to understand why that is. Surely the only difference between a RIS and a RAS is the avoiding action given from other traffic, but I digress.
The time consuming blah about '...resposible for terrain avoidance ..' has, I believe, thankfully been removed from the book. Certainly I've not heard ATC use it for a few months.
As regards the low-level abort, it is still taught during flying training. If a student is unable to fly a safe abort he will not pass his Instrument Rating. The BIG proplem is knowing when to initiate it, not how!
H Peacock