Also multitracking was expensive too and I guess if you were not planning a live album there was no real incentive to pay for the recording and zeppelin has their limited exposure business model. Many other big acts from that era have limited multi track live tapes as well pink Floyd has little in the way of multitracks and seem to have less live tapes on multitrack form then zeppelin do. Black Sabbath is another band that does not seem to have multitracked much. I think their vintage live releases are all from radio broadcasts. Rush did not start numtutracking to any great extent untill 1980. And like page said he never forsaw the CD revolution or even thought people would be interested in the recordings so far into the future. I suppose multitracking for a band like the stones was a lot more feasable s9nve they owned a mobile recording truck so they did not have to worry about the expense.