Chuck,
Looking at photos of Paris-Brest-Paris, Brambilla (professional) had the tube-style hoods in 1951, a lot of others seem to have wrapped the lever bodies in bar tape... In 1956, Baumann (randonneur) had a Herse with the Mafac half-style hoods that we know. They were red to match the tires of the time, he told me. Otherwise, the grainy photos are hard to decipher. Routens' tandem in 1951 either had no hoods or Mafac half-hoods.
No hoods for Opperman (professional) in 1931.
Jan