This is a brilliantly written and very revealing article...i was at an age when the Beatles were a few years into their success and used to watch them arrive at Apple Corps...this is one of my favourite songs...Machine Head was the first long playing LP i bought and Smoke on the Water was a life changer for me...I had the Priveledge of seeing Led Zep perform live in Bishops Stortford and it was the first time i heard Stairway to Heaven...unless you were there one cannot understand...but i have many more songs that could be included all of which hold special memories in my life...everybody will have their own list of songs that changed or made their lives better...but these are three brilliant songs that made you sit up and take note...well done .