Recent datapoints:
-YYZ priority check-in, was not asked about the contents of the ski bag, and the agent didn't ask to weigh it - she just put the tag on and directed me to the oversize drop-off. A friend who also used the priority check-in a few mins after me was asked whether there was anything besides ski equipment in the bag. He said no and that was the end of it.
-YYC, there was a large line at the priority check-in so we just used the self service machines to print our tags. A roaming AC agent scanned them before drop-off and lifted the bags briefly to test the weight, but was satisfied enough that they weren't overweight. Also did not ask about the contents.