Re: Users were left scrambling for answers while critical infrastructure faltered
"In almost every case, development and support were kept apart as separate worlds"
I had the good fortune, when I started in IT, to have a team that did both with in-house S/W. It's always seemed to me that where that could be managed* it was the better system. The worst arrangement was where Unix admin & DBA were not only separate teams but we didn't even set eyes on each other.
* Obviously if it was bought-in S/W the customer's support/operations are going to be separate from the vendor's developers**
** I have, however, ended up debugging a vendor's code that was crashing a client's system but that was because the product was source-available