Let me get this straight: failures on all four engines and a 25,000+ feet drop isn't worrying to you? I mean, sure, that's ok if you're at FL410, but maybe not at, say, FL240?!
Judging some of the comments that SOME pilots have made today, I am increasingly satisfied with the need for ATC to provide some adult supervision in the world of aviation...
Maybe the restarting of the engines was unrelated to the time afforded by a 24,000 feet drop and more to do with the new altitude it found itself at?