From what I have heard, the response time is a minimum going between greys. In reality, the response time will never be that high, however the 2m/s will help with extreme colour changes?

But whatever. You probably know more than me.

Well as you say, gtg is often 2ms so they just write it but if you read on the products own site it often says gtg 2ms and 5ms on other normal changes

Around 3-5years ago they sold screens by screaming, OMG IT HAZ 2MS THAT ONE HAS 5MS OMFG

I'm pretty sure even the best monitors don't even manage Red-White in less than 10m/s.

If i dont remember wrongly Asus just anounced a 1ms GTG and a 2-3MS on colours like Red-White

Well yeah, super duper-best, but you know normal people monitors.

Normal is a strange word But i know what you are pointing at

I have a 60ms/75ms screen and you really can't see the difference. as far as I know a trained human eye can see the difference something around 1/12s which is around 83ms; that's why in movies we use twice that usually which is 24Hz; (and the hobbit is going to be 48Hz!=~20ms) so the difference between 5 and 2 is definitely negligible.

You cant really measure how much a human eye can see. I know I have read this a while back, and the myth about 23,974hz is bullsh*t (i dont know if you are refering to the herpity derpity a human eye can see X amount of frames per second) it only exsists becuse the movie indutry refuses to move away from an old limit (we are talking silent movies old)

Although the delay part i think you might be correct on

Well I don't know your sources but when I learnt optics ehh 2 years go I think, we learnt about the Diffraction limits etc and as a general bonus the lecturer told us some extra stuff(like how holograms work and other stuff) - in which the sampling rate of the eye/brain was ~12Hz...

That seems correct to my knowledge too

If we are talking purely frame rate, the human eye can easily see over 50 Hz. It's a very easy test if you have the equipment. If you have a flashing LED for which you can adjust the flashing rate, like with a waveform generator or something, you can slowly increase the frequency. Almost everybody can still see the separate flashes at about 50 Hz, most people will see it as a continuous light from about 55 Hz and pretty much nobody can see the separate flashes anymore at about 60 Hz. That's why the framerate for televisions and monitors is always either 50 Hz or 60 Hz. I've done this exact thing myself, so I can confirm that this is true.
Movie screens seem to be continuous because of the afterburn effect. The room itself is very dark, while the screen is very bright. So the image of the screen is burned on your retina. The fading effect is slower than the framerate of the screen, so it doesn't seem choppy. But if you look at the screen from the corner of your eye, you can see the frames.

Yeah, ask any notorious European smasher if they can tell the difference between 50 Hz and 60 Hz. The differences are easily spotted.