Electrical Outlets

I'm a EE in a consulting engineering firm and we also do forensic investigation, for insurance companies and lawyers and such.

The breaker in the DJ strip is probably supposed to protect from overcurrent. But then if that was the case, why did you see one with 2 switches that were either partially or completely burned up in that thread?

I don't know exactly what happened in that one instance, but it could have been a loose connector that resulted in excess heating, or just a bad switch, or one overloaded switch. In the last instance, the DJ strip breaker might not have "seen" too much energy, but the individual switch might have been taking all the power and it was too much, or maybe just below the limit for for way too long, and over time, it slowly failed.

Really the best way to do it is to put a fuse or breaker on each outlet. That thread had one as an example. But you're getting into a lot of DIY.