Re: The good old days
Writing and testing COBOL IMS DB programs was a relatively easy process
Three decades of working with COBOL and IMS, and this is the first time I've ever seen someone make that claim.
I suppose it could be relatively easy if the development team is very disciplined. Usually, in my experience, back-office systems like these very quickly become "enhanced" into grotesque shambling horrors. When our customers go to migrate them to our IMS emulation environments, often there's weeks or months of investigating what the various programs do, what source they were actually built from, and how they interact.
But it's true that, as in your anecdote, at least you often got a useful abend and core dump, and could at least identify the point of failure. While that's generally true with standalone programs on Linux and UNIX, and if you're very lucky on Windows, contemporary applications tend to be distributed systems with a huge number of components, many from third parties, and diagnosing their failures can be brutal.