Thanks for your very impressive input. I have glanced at it and plan to look at it much more carefully tomorrow.
I have seen an argument somewhere that 50% can be regarded as a Fib - I'll probably get this wrong but because 1 and 2 are the first two Fibonnaci numbers and 1 divided by 2 is .50 then 50% is a Fib (sort of). As I understand it all the other Fib levels are derived from the ratio you get when you divide one fib number by another, 50% is just unique.
Well I've messed that up but there must be a mathematician out there somewhere who can explain it better - either that or I'm just plain wrong .... maybe I'll go away and look it up.
