I can’t speak for Canada very well but backrooming a card counter would be illegal in the United States. That tactic is only allowed in cases of cheating. However it still has been known to happen. Fortunately in such cases where the counter sued the case the counter won. If I may say I think Canada is more mellow and non-confrontational than the U.S. so I would guess the probability of getting backroomed is even lower there. Although you didn’t ask about it, jumping by a factor of 20 sets off a huge red flag. Most counters who don’t want to attract attention don’t increase their bet by more than a factor of 2 at one time. This is also my policy, unless I feel there is no heat at all.