I certainly didn't think this one up--in fact I read about it in Gierach's
Fishing Bamboo book about 10 years ago but never needed to try it until last week when Les and I were trying Pacchef's little 1 wt cane rod.
When I put it together I seated the ferrules firmly, like I always do, but when Les and I tried to take it apart the ferrules were stuck. Neither one of us could get it apart and it's a very light rod and could be easily broken by mishandling.
I remembered reading about the rubber inner tubes pieces in Gierach's book and ran out to the garage and found an old tube and cut a couple of 2" long pieces out of it.
You wrap a piece around the male and female ferrules and pull straight apart (no twisting on cane!). It worked great and required very little effort.
I now have inner tube pieces in my car, my vest, and my chest pack.