im sorry (sometimes pictures need to be drawn for me) but in the grand scheme of things this is a good thing, except the mm's make a nice profit off of it?
That measure can do far more harm than just "slowing down volume" from dilutive activity: it can literally drive volume down to zero. If order sizes > 25% ADV are outright blocked (Zecco's implementation is this radical), the size of the orders accepted by the trading platform go down exponentially as average volume gets lower each day. If a stock has days of low activity or no activity, the stock inevitably dies unless activity from non-Penson brokers come into the scene.
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