I can't believe I missed this first time around. Such a great thread and so informative
Hedge is a shortened form of Hedgehog. When my youngest sister was about three she started making growling voices in her throat which was her teddy bear talking. As she struggled to say my proper name, Heather what came out sounded more like Hedgehog. My family adopted this and because of my relationship to her and therefore her bear, I became Auntie Hedge. No one in our family has a real name when we're all together....
When I went to Uni I had a boyfriend who adopted the nickname and he introduced me to all his friends as Hedge. So there are a raft of people who went to Cambridge in the early 80's who knew me as Hedge Pound. He also introduced me to the Alan Parsons Project and that's where the quote is from (Pyromania)