I believe that at that length, a single point in speed weighs more heavily than a single cut damage and especially a single stab at such low values. At such a small difference in weight, I believe they each have their own tradeoffs instead of the lighter weapon being counted as a pure disadvantage.
That being said, a one point pierce increase, maybe even two, wouldn't hurt. Good speed and length offsets the poor stab damage. I believe it deals enough damage to stun and accumulate decent damage at a distance, which easily sets it apart from the dao weapons. There are other weapons with even worse stabs that probably need to be addressed at the same time.