There is a question of how risk-averse one is, and people have different temperaments. If it's really a question of how much you want to control the risks, outcomes are never 100% certain--never. It's really a question of degree we're looking at; at least, it seems so to me.
This is a point I had forgotten from your first question concerning the wisdom of going to the Supreme Court. My view is that Bill C-19 is more suspect than Bill C-20, which isn't suspect if taken on its own. Of course, if one goes to the Supreme Court, it would be more effective to send both at the same time to the Supreme Court, but again that is a political decision.