There are a few different ways to do 3way switching, only one way is now approved locally in the Yukon. While i disagree with our local inspections on this, what can you do… anyways inspections wants to see only 3wire between switches now so that the cable contains the identified conductor as well as the travelers.
There are a few downsides to this.
- higher wastage of cable as more cabling is required
- potential to end up with parallel identified conductors less than #1 which breaks a code rule. where this comes up is when you have 2 or more switches 3wayed at the same locations.
- longer install times which contributes to making house less affordable
- annoyed electricians
I can only assume they want this to reduce mistakes and confusion for homeowners, or the inspectors need a refresher course on electrical theory, 2021 revisions of the CEC, and generally accepted interpretations of the CEC.