Am not an engineer of any type, but do have a keen interest in tandems/bicycles.
Have seen and hefted MMC (Grifffen), magnesium (Paketa) and bamboo (Calfee) 0 tandems, but have not yet ridden one.
Have ridden dozens of brands/models of tandems. Some were great, some not so great. While tandem design/ideas have not radically changed since the late 1890s we'd rather be riding one of the newer re-incarnations than the early ones.
Suspension, adjustable saddle/stoker and pilot stems, eccentrics, cross-over drive, laterals, no-laterals all have come and gone and re-appeared again. This time newer materials, whether metal or non-metal, are the big change in our 2-seaters and what is driving the market/sales.
Thought it would be worthwhile mentioning the GTM Advanced stuctures CentrAl. Have read most of their website in English and Dutch (am relatively fluent in both) and they do imply some great things . . . however all their ideas are still being tested/evaluated. Will it be applicable to tandems/components?
'Steel is real' has been the mantra for decades. Non-heat treated alu had been used but was quite flexy. Then Cannondale presented heat-treated aluminum and that took a bite out of the steel market. That was followed by titanium, magnesium, carbon fiber and bamboo or combinations of various metals/non-metals.
As stated earlier, have ridden steel, alu, ti, c/f , Isogrid, lateral/lat-less twicers, etc.
If it wasn't for someone inventing matches, we'd still be rubbing two sticks together to make fire.
We all have our preferences and fortunately there's lots of choices out there!
Put your $$ and butts on what your team prefers!
Pedal on TWOgether!
Rudy and Kay/zonatandem