Don't know if they did this in the past, but this year the WC cables have a special coating on them. The coating is slick enough that it can be a job to keep the restcord from slipping if you tie it on (although it's not impossible - they actually give you instructions on how to tie one on on their website, which I assume works). However, they advise against penetrating the coating and tying a the rest cord through the cable. Since I had the cable clamp anyway, I decided to use it rather than tie the rest cord on.