Frangible : it depends on the definition of " as intended ". I took it in the global sense , intended to prevent the 2 a/c factually hitting each other.
From what I was told and understood :
In he current system (7.0) The initial RA sense will not be reversed until it has been displayed for at least nine seconds (unless the low Mode S address aircraft has a vertical rate higher than 2500 feet per minute and acts contrary to the RA). But : if both aircraft are going at the same rate towards each other ( one following its RA and the other one acting against it ) No RA reversal occurs. I believe that is the problem , But maybe we are talking about the same thing.
I understand Correction Proposal 112 E should rectify this and allow sense reversal at all times . ( decision on this next December I believe ? )