Since type 3 clematis are typically hard pruned, it should be fairly easy to untangle from a trellis system.......at least I find it to be. Once the clematis vines have been cut back to the low level, you are free to cut or pull the remaining upper vines free. I grow mostly type 3's and this is a pretty normal routine at this time of year before the vines start budding out too much.

By the same token, I find type 1 and 2 clematis less easily managed on a trellis because actively growing vines will be present as well as dead vines that need to be removed and it becomes harder to differentiate between the two.

Oh thank you for that feedback. I am picturing digging and pulling and yanking out hardy vines from the system and apparently it is not that cumbersome. Do they pull away easy? Are you able to keep the old wiring (or wire alternative) or does that tend to pull away with them?

" Do they pull away easy? "

Yes. As the vines are dead and usually quite brittle at this time of year, they pull away rather easily. And if they do wind around the trellis or wiring system, just clip them off at that point and remove the remnants manually.