Threaded headsets loosening?

Joerg has complained about classic headsets that won't stay in
adjustment. As I said, I had that problem on our tandem and solved it
with an aftermarket Growler Headlock:
http://www.bikepro.com/products/headsets/hset_acc.html

But Compass Bicycles claims this works too:
https://www.compasscycle.com/shop/co...adset-spacers/

I have no experience with it. Just thought I'd pass the idea along.


--
- Frank Krygowski