I don't recall running any TPKs as a DM, but I experienced one in the climax of amy first Living Greyhawk adventure. It could have been a rather tough experience too, as most of us had never played together beforehand... but we all had so much fun, we made new first level characters, and struggled on into the next Living Greyhawk module.
Those characters survived 2 modules until they hit a TPK.
On our third LG characters, we actually got some semblence of tactics together and actually did quite good... until we got disillusioned with LG in general.
Those characters survived 2 modules until they hit a TPK.

On our third LG characters, we actually got some semblence of tactics together and actually did quite good... until we got disillusioned with LG in general.