I didn't mean actually running away. I just meant flee as in escape. I was thinking in terms of just briskly walking away from the checkpoint. Of course due to the answers of people like you I see that even that is not necessary.

Well this is my research. I dont know of a better place to find this sort of information, especially in a way that is up to date, reliable, and reflects the actual reality of the situation (as opposed to propaganda like on the TSA website). Thanks for the link. I will definitely check it out.

Until recently I was thinking along the lines that CATSA was much, much better than the TSA. That there was no comparison at all, but some recent posts had me rethinking that. And I didn't know until recently that CATSA also stuck their hands in your pants to do a "waistband" search. I haven't flown to Canada myself for a long time so all I can go by are traveler reports and US based travel tends to dominate on this forum. So I couldn't find much info on the subject.

As far as the scanners go I don't personally have any safety concerns. It's strictly a privacy issue. If I was departing from an airport with an ATR system I would probably go through even an xray scanner if I thought it would reduce my chances of getting groped.

I have read contradictory statements about the invasiveness of the CATSA patdowns. Since I doubt I could get the CATSO to agree in advance not to touch my genitals or butt crack or stick his fingers down my pants (the fact that the US TSOs actually pull out the front of your pants and peek down is beyond offensive). I think the sheer horror of TSA's insane procedures may have actually over-sensitized me to the whole thing so that even the slightest transgression will prevent me from flying.

If necessary I am prepared to take a train/bus all the way down to Mexico and fly out of Mexico City, but that would mean 3 days of overland travel. If only I could be sure that I would not be fined or prosecuted or no-fly listed for leaving the checkpoint I could at least attempt to fly out of BOS or MHT before resorting to departures from neighboring countries. I'm still considering those options. With this new information I can make a much more informed decision. It looks like YUL is actually a pretty good option for me. It's an interesting compromise between the certainty of Mexico City and the uncertainty and risk of my local airports. With Canada, while there maybe no guarantee that I will be able to actually make my flight, at least I do have a guarantee that I won't be arrested or fined.