Touring bike, for those really steep get off and push hills, it was good to have the rear brake on the left,
to hold the brake on while i'd catch my breath , & let my heart rate relax.
Coaching Cyclocross Racing, Simon Burney,, Author, of several book editions on racing CX,
suggests left rear scheme too, as that lets you brake at the last moment,
while on just the left pedal, before getting off, running, and lifting the bike to leap barriers , etc.
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