nichodemus, either way the increase in points will cause people to go for them. If you could write a normal comment for 2 Ap, or you could write a merit worthy comment for 100 Ap, a lot more people would go for it. It would only take about 20x the amount of time, yet you get 50x as much AP. That would make it worthwile to at least go for it even if they are rare.
And this will die down after people realise that they don't get merits easily. It used to be so that a tiny paragraph got you one in 08. Not anymore.