Thinking about this some more, I think I understand the logic. What I couldn't wrap my head around is the fact that they supposedly had this new revolutionary hairspring on the Daytona for at least four years before they made any mention of it, then suddenly decided to color it blue, and prominantly mention it in their marketing. But I now have a new theory.

If I'm a manufacturer, and I want to field test a significant poduct modification, I'd pick a lower volume model to put it on, and I wouldn't tell anyone...in case problems came up during field testing. Then I'd sit back and see if the modification fucntioned properly, see if any service issues arose etc. Now if the field testing went well, I'd feel comfortable telling the world what I great new revolutionary idea I had...all of this seems to map plausibly with how the Parachrom hairsping ended up on the 4130 for years before Rolex made any mention of the fact...and when the Marketing people were tasked with how best to market a "boring hairspring" someone probobly came up with the idea that putting the oxide coating on it wouldn't impact performance, and would give a blue color which would look snazzy, make for good marketing copy, etc. And they likely decided to give it a sexy new name - "Parachrom Bleu."

I'm trying to run this by my contacts to see if my theory in any way maps to reality. Thoughts?