Thanks for the discussion, and many more questions have now popped up!!
Now onto another though, I notice alot of the modern airliners equipped for long range ops mainly utilise winglets, these aircraft obviously spend the majority of their time in the cruise. I believe winglets are used to reduce induced drag generated from the mainplane, however if these aircraft are spending the majority of time in CRZ (thence low AoA = low induced drag) how are winglets beneficial as all i see is a potential parasite drag increase. Im not out to reinvent the wheel, and i trust everything the engineers/designers have done. I am however very interested to know the reasoning behind this.