A bit of an update on my oil consumption issues. I emptied the catch can last Friday and it was full of nearly pure oil. I contacted Griffin and their initial thought was to swap PCV plates between their VWR-equipped A3 2.0 Quattro shop car and my car to see if that made a difference. That was originally going to be done this afternoon. I decided to conduct an experiment and emptied the catch can, went for a 100 mile freeway drive, then emptied the catch can again. This time the contents of the can were a reasonable 50ml of fluid with the expected composition of oil, fuel, and condensed water vapor, i.e.: chocolate milk.
Griffin's hypothesis is that the oil was overfilled somewhat and this caused the PCV plate to siphon actual oil from the sump and not just the blow-by. They had previously experienced similar behavior in their shop car, which they corrected by removing excess oil from the engine. My car had been with Griffin to replace the valve cover seal to fix an oil leak, and the repair was completed a couple of days prior to the HPDE event. Griffin indicated that it is not inconceivable that the tech overfilled the oil a bit when completing the repair, or alternatively that the oil was correctly filled but that it expanded once the engine and the oil warmed up to race temps.
Their recommendation is that I arrive at the track with the oil a ¼ to a ½ quart low, and monitor and maintain the oil level during the course of the event. I'm going to perform an additional experiment in the next couple of weeks and go for a 75 mile canyon run to see what happens.
Contents of catch can after 20 minute track session and 100 mile drive home
Contents of catch can after 100 mile freeway drive