Dario's direct involvement in physically making a particular Dyna or Radius is captured on a long thread / post here:
https://www.velocipedesalon.com/forum/f ... 44-13.htmlHe said something to the effect of, "Yes, it's possible." As a side note, it was kind of mesmerizing to read his direct responses to readers questions.
So at a minimum, he had direct involvement in the design, etc., and there is a possibility he may have laid hands on a particular frame. Basically the same could be said of a Pegoretti; his company, but he employed craftsman to help produce frames.
In any case, they are all sublime riding bikes, and I'm very pleased to ride one!