They used to do TDD but found it to be "too slow, foreign, and dogmatic". Instead, now they are just "ready for bugs"
"Alarms on everything"
"Pipe them to email, chat, and SMS"
"Bug fixes are a top priority"
"Tests are fine, but not compulsory"
Now, in the same book where we report on that, there's a meta-study compiling all of the evidence that we had in 2010 about test-driven development. And it turns out that on balance, there is no evidence that it has any impact up or down on the quality of software or the speed with which it's produced.
At 55 minutes: "We prefer the system to fail than try to do (xxx) prevention. If you think about it, tests themselves are not lean in any way whatsoever. Because tests are there just in case something goes wrong. Any time I use the word "just in case" or "it may be necessary" I've now moved outside the lean/agile world. I'm doing something almost by rote. I really want to be just in time in these sorts of things. I'd rather have a system fail fast than do (xxx) prevention. And so that's why my unit tests have gone away, because I'm deploying twice a day. I have my business metrics to tell me when I've screwed it up. I don't need to write those tests."
At 26:40, gave up on tests. Unit tests are a design smell. Tests optimize for permanence. They create coupling and stasis. The mean time into resolution was the most critical thing. They got very into measuring things at a granular level.