First, I hope you feel better Holoz!
On the detection, its more about stating what the community believes the rules should be. Once rules are made, then of course people can choose to follow them or not. I believe that 95% of most players will abide by these rules if they know they are the rules. What we can do to mitigate the other 5% and how big of a deal that is in actuality, can only be determined after the rule is in place.
Many people will argue that some will cheat, so basically don't try. I am not in that camp though. I believe that we set the rules we want, then assess the outcome of those rules. And then if its necessary to adjust either the enforcement or the rules, then we do so at that time.
Put another way, I would rather try and fail; then not try and definitely fail.
And on the date, its a proposal to change the terms of service which implicitly means that it can only be in effect once that change is enacted. We can't ever go back and change rules retroactively.