Engine braking and oil consumption

[SoCal LS-L]

Heres a question that has been on my mind for a bit, as I still routinely drive up and down the Mt Rose pass at over 9000 feet.

I have noticed that my car loses oil at a much faster rate when I drive this mountain road..... and I do not ride the engine in high RPM's while climbing. My car does not burn oil on regular freeway trips either. The only thing I can think of is my tendency to keep it in "3" whilst coasting down either side of the mountain. I do not like to ride on my brakes and the SVX has a tendency to want to get into triple digits during downhill grades in Drive.

The difference in oil consumption between flat land travel and mountain runs is massive.... should I be concerned that my valve seals are shot... or do you think that the problem may be more benign.... such as a PCV issue? Has anyone else noticed excessive oil loss due to long duration engine braking?

The Reno side of Mt Rose is about a 25 minute long coast down a steep winding grade, and I usually let the engine handle most of it. Im not that familiar with the characteristics of HO engines..... should i just leave it to the brakes?