That's slippery slope logic. If the pricing is right at
   1s, why pour money and talent into getting it right at 
   100ms?

I'm saying there are negative externalities[1], which are known to cause market inefficiency. Negative externalities typically look like "slippery slope" arguments, when in reality there is an appropriate level of penalty/tax/etc that restores efficiency.

   Meanwhile, you're effectively vouching for a comment 
   that models the markets as a closed system of people 
   dividing up a single pot of money. Isn't it plain that 
   such a model is wrongheaded?

I'll concede it's not zero-sum, but surely you also will concede diminishing returns to liquidity. I'll also concede that my original "money sink" comment was hyperbolic & inflammatory.

[1] http://economics.fundamentalfinance.com/negative-externality...