I don't know if this bug affects Phenom II chips, but I've been running a Phenom II for 8 straight years in my primary desktop with nary a hiccup. Rock solid reliable. Guess I haven't been running the "correct conditions" for a crash?
You could also have a BIOS update with the workaround already baked in, or a chip that has the later silicon without the bug...
(I also had a Phenom II for many years without any mysterious crashing problems, even though the chip was the correct revision and there was no BIOS erratum workaround enabled.)
(While it doesn't apply for this specific example, it's still the reason why one generally will see microcode-fixed errata go away rather quickly, independently of BIOS updates)