Originally Posted by: equatorHey.
I really apreciate you taking the time to answer this question.
But unfortunatily your theory fails in the fallowing:

I did say I was a bit rusty...

However, I have found this definition that, although very brief, should explain it

http://www.google.co.uk/search?hl=en&lr=&oi=defmore&defl=en&q=define:Altered+chord

Think it's time for me to step away from this conversation and let someone who's not forgotten half the stuff have a go...