Just to finish off with this thread, I originally asked, '...why have Michelin, who know a little about tyres, brought out new bias-ply tyres for classics?'
As I said earlier in this thread, I wrote to Michelin UK asking the question and despite three reminders they have not responded.
So, what conclusion can we take from this? For me, I would say these new Michelin classic tyres are X-plys for marketing or tooling cost reasons and not for improved performance.
Therefore, my conclusion and from my experience with both riding X-plys and Radials on my 3C, the Conti Radials, are superior in all areas on the road. I cannot comment about race conditions.