Neuroticdan,
If you see that they are sure to report you or officer on duty tell you that he is going to report your shortfall, just try to convince the officer that you are fully prepared to stay in Canada for next two three years without coming out. Some officers want to see / hear these things to justify their decision for not reporting a person, it is better than be quiet and let them do what the rules says.
Very bleak chance but good luck anyway.