alt Hacker NewsStand outside an engine test cell for a while and tell me that maintenance crews don't deal with emergencies. I'll bet they do so more often than pilots, we just don't hear about it because there are no passengers at risk. Nobody is going to make a 'Sully' like movie about the maintenance mechanic that spotted an issue with a part under test before it led to one or more catastrophic failures. They're more likely to make a lawyer the lead than the mechanic.
This is not just filling out reports and looking at stuff, they're in no way comparable to your local garage mechanic (and not to dump on them either: they too have to deal with out of the ordinary situations).
The responsibility issues are the same as with the pilots as well, they fuck up people die.
I didn't say there aren't any emergencies, but the emergencies are not on the same level. And I said they're highly trained, you don't need to convince me of that. Nor do you need to convince me they're important. Those are entirely separate issues.
Also what fraction of engine test cell use is for engine maintenance? Is it a big amount?
But if that kind of test goes wrong the main outcomes are "hit stop" and "oh no it's too late". An emergency like that is not where much of their expertise is needed, their expertise is in other parts of their job.