Greg talks about writing songs of "universal truth" for King Crimson and ELP, and tells us about his most memorable stage moment (it involves fireworks).
The Scorpions and UFO guitarist is also a very prolific songwriter - he explains how he writes with his various groups, and why he was so keen to get out of Germany and into England.
If counterpoint and polyrhythms are your thing, you might love these guys. Even by Progressive Rock standards, they were one of the most intricate bands of the '70s. Then their lead singer gave us Bon Jovi.
Did they really trade their guitarist to The Doobie Brothers? Are they named after something naughty? And what's up with the band name?
These overtly religious songs crossed over to the pop charts, despite resistance from fans, and in many cases, churches.
The stories behind "Whole Of The Moon" and "Red Army Blues," and why rock music has "outlived its era of innovation."