In the glory days of the RA1 (2005 to 2009? ) there was a saying about tires -Thin to win!
seemed like the tires were fastest just before they would show cords.
Life was simple then. Shave to 4/32nd and run them till they get so thin they cant keep the air in.
That is what a spec tire should be.
We used to say the RA1's sucked, but they sucked for a long time.