I think only one needs it to utilize it. If your tv doesn't and your player does, you're okay.. and visa versa.
I'm not too educated on it, but I read that it may be better in many cases if your player does the 3:2 pulldown.
..that's just what I read a few days ago, anyway.
Adam is right.
When you use a progressive scan DVD player, the player output skips the 3-2 sensing and optimizing capability (if any) in the TV. (As far as I know all DVD players have 3-2 pulldown regeneration for film source material.), When using a non-progressive player or a progressive player in interlaced mode (or a VCR or LD player or when viewing ordinary brosdcasts etc), the video signal goes through the TV's 3-2 pulldown circuits (if any).
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