When I brought in a feral litter of 5 months old last spring, they all used the post automatically... I didn't even show them how! Cats naturally like to stretch, and I think the sissel rope wound around the post was more of a simulation of the trees they would scratch outside anyway, than a couch ever would be!
And yeah, carpet runners never worked for my kitties. Tin foil worked for Nebbie, but not for Zinny... in fact, Zinny -likes- the crinkle and shiny of it!
(they also used the litter box without my instruction, too!)