How does one substandardly shuck an oyster? You either crack open the shell or you don't.
You crack the shell without a) damaging the meat b) losing any of the juice and c) getting any of the shell dirt and detritus in the meat and juice. Then you separate the oyster cleanly from its shell without leaving any bits on the shell and again without damaging the meat or losing any juice.
I promise you that if you have oysters on the half shell anywhere that serves good oysters, and there are many such places in Houston, and then sample oysters on the half shell prepared by the gentleman who was working the bar the evening I visited Pascal's Manale you will immediately realize a stunning difference.
It's sort of like sushi rice. If you've had good sushi rice you may think you have a pretty good handle on the difference between good and not good sushi rice. But until you have sushi that features rice made and assembled by a master you will have no way to know that good or even very good is simply not good enough to someone whose very essence of being is inextricably connected to what he does all day.