The 47PFL9632D is designed and sold as a high performance television. There is a lot of processing that goes on within the set to improve the picture. This takes some time, somewhere close to 100mS. It is impossible to bypass this circuitry in the TV set. Sets of comparable quality from other manufacturers have roughly the same amount of time for video processing.
Dedicated computer monitors do not process the video in the same way, their circuitry is very direct, sending the signal straight to the LCD panel or CRT without picture improvement processing, hence no delay on them.
I read the thread on the forum linked below, and the comparisons are not really fair, they are comparing dedicated PC monitors (that do not process the signal at all) with TV product which is designed for best possible picture quality.
You are correct that the TV synchronises the audio to the video. If you bypass the TV for audio by going straight to the amp, you will hear the sound straight away, but you will then be slightly out of sync with video and audio.
I don’t know what that will mean to you, it tells me that is how the TV is and there is nothing that can be done to change it.