I sat down to total up the costs of the last build (one for me) and I have to admit that the not so high cost side of this thread has a valid argument.
It appears that part of what drives up the cost of my builds is that when faced with a choice I'm more prone to choose the better equipment........as in "aww it only costs a little bit more".
I find that I use things like Avid flak jacket cable instead of generic and lock on grips instead of less expensive.
So I guess that the 2:1 cost rule doesn't have to apply to each and every build. I was breaking my own rule on comparing same to same.
On complete bikes, manufacturers use all sorts of tricks.....this is how you fine a Deore front Derailleur on what is other wise an XT bike.