David Damerell wrote:

Quoting NYC XYZ :
Hmmm...I thought it had to do with the mechanics of the pull of the
cable...a V-brake seems more powerful, from a mechanical POV, than a
cantilever...I can't quite imagine in my mind's eye the same difference
between a V-brake and caliper brakes operationally, but I have heard
that V-brakes are second only to disc brakes.

You might hear a lot of things.

On a single bike, any brake of sensible design, not abysmally low quality,
competently installed and adjusted, will lock the rear wheel (rear brake)
or lift it (front brake).

You cannot have more braking than that, so the theoretical brake "power"
(which tandems find out, with surprising results) is quite irrelevant.

An interesting (to me, at least...) data point is that I designed my
new tandem around regular road caliper brakes, never having been
really happy with the performance of canti brakes on my previous
tandem. The stopping ability of the new tandem is considerably better
than the canti brakes (and presumably better than V-brakes with cable
pull adapters would be).

David's right - there's no braking test platform better than a tandem.

Mark Hickey
Habanero Cycles
http://www.habcycles.com
Home of the $795 ti frame