Todd's explanation relates to poor understanding of hydration and close spacing of villages. My hypothesis is a bit different: fad and fashion. Centerpull brakes come into fashion and go out of fashion. Water bottles migrate from the handlebar to the downtube. In the 60s the fashion was to avoid braze-ons that might weaken the frame; in the 70s it was braze-ons, presumably to avoid marring the paint (or having things rattle loose, per French randonneurs). See also discussion on "retro" cranks. :-)
harvey sachs mcLean va. +++++++++++++++++++++++++++++++++++++++++++++
Marc St. Marting wrote: I think Todd Teachout posed a viable theory in his 4/26 post related to Ray's Herse:
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Regards.
Marc St. Martin
Livermore, CA
USA