FWIW, we walked into OM on a Friday with no reservation, albeit early in the evening, were seated immediately, politely informed about the menu, ordered at our leisure, a course at a time, and enjoyed the food thoroughly.
I am a wine professional by trade, and the wine service very good, IMO. "Seasoning" the glasses with a very small amount of wine is an important and oft overlooked step in the service of a delicious wine whose aroma and initial taste may be lost due to the health code-mandated cleaning the glasses receive. Keeping the wine off the table is simply a way of keeping it out of your way, and shouldn't even enter your thoughts unless the wine steward is not doing their job by keeping your glasses refilled as they empty (and this does not mean pouring an ounce every time you have a sip, BTW).
Also, why "just pour off" the last 2 oz when it would affect the way the wine was sensed or developed in the glass?
The aim of proper wine service is to get you into the best wine for you, then let you enjoy it to the fullest in the least intrusive way possible.