Why does it matter what was their reasoning?
At the first approximation 10 billion dollars was left on the table, this is not a great job of underwriting.
Sorry, that's totally wrong. It would have made extra 38% for the company if IPO price was $93. It's not fair to say that GS did a great job of underwriting if price moves up 38% when trading starts.
Switch to the normal broker and stop using cheap routing strategies. There is no way HFT could be blamed for your problems. If you are using the right technology *nobody* will see you order until the trade happens.
I am not trying to protect the current market structure. I am just saying that in this particular case there is no evil hft using some secret order type on nasdaq evolved.
You think about off market trade as something when you and I have lunch, decide to to "exchanged goodies" shake hands and...