Yes I will eventually be going 700c, (see post #14 above). it's fun watching ideas get kicked around so feel free to continue.

I hadn't thought about center pull brakes in a 27" to 650b conversion but I agree that the posts would probably be to low for the pads to reach.

Was the 700c standard around before the 27" standard and we (americans) wanted an inch standard to match the rest of what we had? They are so close I wondered why have both?