I just got a notice on Facebook that a page on doing this has been added to/ updated on sheldonbrown.com.
http://sheldonbrown.com/upgrade.html
It has the basics. But yes, C&V talks about this all the time.
I don't recommend doing it, personally. Nothing wrong with 12 speeds. Better durability of 6/7/8 speed chain and maintenance is easier. Not to mention that a new drivetrain can be quite costly!
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The bicycle, the bicycle surely, should always be the vehicle of novelists and poets. Christopher Morley
Last edited by Standalone; 04-25-12 at 09:02 AM.