I did my first DE ever at the Glen last year. I loved it... had a great instructor that helped me keep improving throughout the two days. My similar photo is my computer's desktop background... attached here.
I seem to remember hitting 12x-13x MPH on the long sweeping curves/straight approaching the BusStop - my instructor would be leaning over and watching the speedo and pushing me to improve on each lap. It got to the point that the accelerator was pegged to the floor from entering the first curve off the main straight until just before the BusStop.
When I first started, I could not see any possibility of holding speed through the BusStop but by the first afternoon that was a "no drama" spot too.
Ad, I had a similar experience with the boot and if we're thinking of the same corners (plunging downhill CCW followed by sharp uphill CW turn into a short straight) then I'm with you. I got to where I could drive them OK, but I never "got it" there like other parts of the track - it was really easy to end up plowing through the CW turn uphill. A guy in my event ended up trashing his car rear-first against the rail at the bottom of that hill...
And I managed to have a 4-wheels off at the end of that short straight right after that spot... luckily nothing but grass was encountered there
!
Despite it being a green run group, I did have fun passing our more expensive siblings (we seemed to be able to carry more speed through of the corners), FWIW.