MaxAngle
The MSA printed on most nav. logs is only good for 10nm either side of the route and an emergency descent from 350 to 100 is going to put you at least 30-40 miles off track if you turn through 90 degress.
I think this post is materially incorrect. All the Nav Logs I know give MSAs far higher than 10nm either side. An emergency descent turn to either parallel course or reverse course is not going to take you 30-40 miles off track unless you keep heading out there. I would hope if in a mountainous region a decision is taken early about blundering on into terrrain! Meanwhile, I hope those who descended rapidly through everybodyelses tracks got down OK! I'm not sure TCAS could handle it.