FPS..Display HZ and vsynch

You have given us a LOT of information , and we appreciate it.
I would like to make only one more statement.
Time to start building a simulator and show us all.
"put up or shut up"

3D would probably only make you better if the field of depth helps you to make more accurate judgements while driving.
If you have eyes that are sensitive to high frequency flicker, then 3D glasses can tire your eyes. But it is not an issue for most people when at 60hz. However, when 3d is not ghosting or having artifact issues, it does make for an interesting experience. Add Trackir or something like it to the mix, then you will have somewhat the same experience you would with the Oculus Rift.
And I do see your point about input lag because, form what you posted, it seems it can be quite long. However, if there is one it doesn't appear to be a problem with my lousy driving!

You looked very good in the Watkins Glen video. I am very familiar with that track. Very impressive passing down the front straight. It means you executed the last turn with near perfection.

All the lags do add up and can be an issue if your GPU allows FPS to fall below 60 and your using vsync as it cuts refresh to 30. But most people can avoid that by cutting back on the unnecessary eyecandy.

The biggest issue for iracing is the ping...base pretty much on distance from server. Hopefully they will add some additional servers. I am sure a few Brazilian hot shoes have run into me because of their high ping.