On my first visit to China in 1972
You may be able to scotch a rumour knocking around China in the early 90s.
The Chinese were having trouble with the TBO of the Klimov copies so they asked Rolls Royce to send out a team to assist them. They brought out their original drawings of the Nene and put various things right.
Apparantly they stung the Chinese a packet for assisting them to fix illegal copies.