After a moment's thought I had the idea:
1. I built the chain from again.
2. The chain was sprayed with a general purpose silicone oil.
3. The chain has been pressed a few times.
4. Excess oil was removed with a paper towel.
5. The blind was reinstalled.
Lo and behold, the curtain goes up and down like butter and is no sound.
The shade itself obscures very good.
Despite my engagement with silicone spray, I give it 5 stars because the price / performance ratio
and the blind met more than its purpose.
The silicone oil can be found here: öl-200ml/dp/B00EOIY69A/ref=sr_1_fkmr0_1?ie=UTF8&qid=1386339640&sr=8-1-fkmr0&keywords=Gyrolon+universal+silicon+%C3%B6l