hpst That's a good observation that I prefer TN! For some reason they give me "paper feel" and comfort, however they are useless with my MACs, so when I have to be on the Mac it's kinda same if I use it or plug to external TN.
It's been almost 2 months with this chromebook and it's irreplaceable for me. It's interesting how after 6 years for first time I see a screen without problems and now I hate when I have to look at any other screen even for short periods.
For me definitely contrast and sharpness play bigger role than flicker.
I found some patterns that makes the chromebook less usable!
On my external monitor I use brightness and contrast super low. I can bump the brightness to high as long I keep the contrast to 0, however if I do the opposite, increase just contrast my discomfort is instant.
TN panel gives me "pixelized" screen that I prefer. If i set high resolution/increase scale the screen becomes smooth and discomfort starts. For some reason this does not affect fonts only but watching video or pictures too. Colors give grayish vibe, it's not the shimmering white.
Even with the good software setup I can't tolerate glare anymore! It doesn't matter if it comes from a florescent light or a window. I noticed that in my office there is very big difference in reflection and contrast in the morning/noon/afternoon and my comfort level varies on the same hardware.