> The problem is not that dev-owned testing is a flawed idea, but that it is usually poorly planned

In our case there was zero plan. One day they just let our entire QA team go. Literally no direction at all on how to deal with not having QA.

It's been close to a year and we're still trying to figure out how to keep things from going on fire.

For a while we were all testing each other's work. They're mad that this is slowing down our "velocity", and now they're pushing us to test our own work instead...

Testing your own work is the kind of thing an imbecile recommends. I tested it while I wrote it. I thought it was good. Done. I have all the blind spots I had when I wrote it "testing it" after the fact.