I agree with you on the front/rear argument. The 112mph Rourke/Hope human powered (slipstreaming) bike in the link above has only a front brake and fixed gear. However, using its front hydraulic disc brake allowed the rider to slow down from 112mph on a sandy beach without lifting the rear wheel or losing traction.
Modulation, accurate control of the braking power, "feathering" (no idea if that word is used in USA) allows you the best chance of survival in a critical situation.
Even a V brake has far better modulation than a caliper, cantilever or even U brake. Due to the extra leverage from the brake arms there is less leverage required from the lever on the bars. That means a
longer cable pull, that means
less cable stretch, that means much better life saving modulation.
Cable actuated disc brakes use the same lever as V brakes, plenty of cable pull (low leverage at the bars) so they have a comparable stretch and drag but with the added benefit of being unaffected by imperfect/dented/bent rims, water, mud, oil from the road, so they can be closer to the disc (they move less) for even more pressure which is what
cleans the disc surface.. And they don't wear down the aluminium rim by scraping grit into it so your wheels last. The disc is steel, never wears down noticeably.
Hydraulic actuation just gives you a drag free, stretch free, virtually maintenance free system but the difference is like night and day. True one finger braking and modulation like nothing else.
My refurbished 20 year old Hope C2 hydraulic disc front brake cost £15 ($20) from an eBay seller. $20 to stop me ending up under a truck sounds okay to me.. Even $10 for a V brake would be money well spent IMO compared to dumpster erm I mean caliper brakes. Maybe I'm just fancy, but I think overkill is better than being killed.
Spend your $10 on a wreath if you want.
p.s. there are plates that you can bolt on, so you can mount V brakes and disc brakes to old frames that only have the caliper hole.
