Well, this argument is that it's broken, if we're fixing the monk in general. So, if it's with a monk with full BAB, then it's a pathetic 1d6, but with a +1 BAB and a -1/-1 Flurry.
Then at 5th it would be maybe a 1d6 still, but with a +5 BAB, and a better flurry...
The idea is to rebalance...