http://www.xbitlabs.com/articles/other/display/response-compensation.html
Some quotes:
The ISO 13406-2 method to measure the monitor’s response time as the total time necessary to change the state of a pixel from pure black to pure white and back again brings but very little information about the real performance of the monitor and easily misleads the user.
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The problem is that the response time value obtained by this method is not the maximum and even not an average, but the minimal speed the monitor can have.
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Moreover, the designers of LCD matrixes found it easier to achieve very low response times exactly when it is measured with the standard “black-white-black� method. As a result, the so-called “fast� TN+Film matrixes with a specified speed of 16, 12 and even 8 milliseconds appeared. Alas, they are not 2-3 times, but only 25-30% faster than the older 25ms matrixes because the response time on halftones has in fact remained the same.
There’s also differences in the technology that makes TFT response time and CRT refresh difficult to compare:
The transistors in a liquid crystal screen, he said, have to “hold” the aperture open to allow the light to pass through each pixel. That’s different from a CRT monitor, which pulses each pixel to generate the light.
With LCDs, he said, the eye and the brain continue to see light in between each frame, while with a CRT there’s a period of lower or no light in between each frame, and that helps the brain to process the movement.
All that said there are TFT monitors that works really good for gaming, though I don’t have one myself.