For the question about if CATSA's website is accurate; "kinda". It does depend on the volume.
I believe CATSA measures the time from when you show your boarding pass at the beginning of the line cordon all the way through to when you scan it before putting your luggage on the rack. Therefore, if the line is stretching around the airport terminal, it doesn't take into account for that portion, just until you get up to the CATSA agent at the line cordon that tells you which line to go into. So the time leading up to the front of the line could be 2h, and 10m from front of line to the boarding pass/security scanning and CATSA's website would only say "around 10m"
(I could be wrong, so feel free to correct me if anyone else has a better sense).