Videotron's official tethering policy
Videotron's Terms of Service (ToS), available at Terms and conditions
, does not specify if tethering is permitted on their network or not.
The Videotron FAQ's, located at Internet on your mobile
, does not provide any documentation either.
After contacting Videotron's support, they informed that as long as you subscribe to an "Internet on your mobile" plan tethering is permitted on your Android device. All data used will be counted against the allowance of your plan and if you exceed your plan allowance you will be charged overage fees. They were unable to provide any documentation of this online but provided the following link.
Limitations to our support
Services that we donít support
Connecting the mobile phone as a modem (tethering)
So while you are permitted to tether if you have issues their support will not help resolve the issues.
If you wish to tether on Videotron's network please make sure you have a data package attached to your plan.