when dealing with an engine failure things tend to move rather slowly giving adequate time for an ATC arranged separation
A crew I knew had an engine rundown, at night, FL370. There was the startle factor, and they went for the Engine Malfunction analysis first. Very very quickly they got the stick shaker. And then what. The recovery at FL 370 will lose you >2500'. Thinks move faster than you think. And in that stall recovery you get an RA; then what do you do? Meanwhile you haven't contacted ATC yet during the WTF moment. There's more to TA only than an engine failure scenario. Read the Eurocontol bulletin as to the advisory reasons for TA only. Reflecting on the various airline training I've had over a career the appreciation of the TA Only selection was mis-understood and thus ignored and pilots were left in the dark; no discussion. If it wasn't in the checklist then it is not necessary attitude. When I put this scenario to a Boeing pilot I was told "I think TCAS will take care of it, but perhaps we need to consider it." IMHO thinking is not enough in a scenario when you need to be certain. I suspect he was thrown by a Eurocontrol advisory that had not drifted across to the USA yet, where they consider they rule the roost. Except they don't and that is why the Boeing Emergency descent checklist has 10,000' in it. Why? Trans Alt in USA is 18.000'. At 10,000' above UK you are in controlled airspace where the law says you mustl be on STD at a FL. Once, in the RST sim, I was told it was wrong to descend to FL 80 over UK. Hm. I doubt ATC will let you swany around at 10,000' amongst everyone else at FL's.