Gigabit vs Fibre Channel Discussion

My friend Mike has spent a lot of time working on large networks and SAN devices within corporations and government organisations here in Wellington and around New Zealand so when I get curly network questions I usually turn to him. The other day I emailed a really quick question, what provides the most cost-effective high bandwidth network, fibre channel or gigabit?. He soon replied gigabit and then tacked on the end hold on a minute, just writing some notes...

His notes turned out to be a two page series of observations and findings that were so interesting that I asked him if I could put this up on my website so that I could refer others to it. I have edited pieces for clarity and added a bit of background but more or less I have copied things verbatim from his emailed reply....