But man..........it's so worth it!! Seriously...........Jimmy Page's study on his use to not just the pentatonic and superior following of chord changes and pre-bends and great use of chromatics but his energy and tone as well!! I keep on and on about your Buddy Guy solo tutorial......this Jimmy Page lesson may be the best one out there!! This song is over a half century old (for Led Zeppelin) and look and hear how so very timeless and great it is standing up to time!! You're absolutely correct on what you state at the beginning here, T.F.........anyone who really wants to shine their chops and leapfrog into the next level of superior guitar soloing needs to bear down and get all of this solo down plus dedicate themselves to understanding where it's all coming from and then embrace it all into their own playing!! Absolutely a masterful instructional piece here Tom.......slide and soloing and the real energy and feel of this great rock and roll band!! My fretting hand is aching but I'm wearing a big smile!! Jim C.