I'll answer now briefly, and talk more later.(posted 10011 days ago)It is pretty obvious to an expert player which difficuly settings were used when you watch an INP playback. In the case of Williams games you can even watch the player set the difficulty settings before he starts playing. Of course, the player would have to set the difficulty sets during the inp recording, which is supported by the newest versions of MAME.
In the case of centipede the spider is a lot more aggressive, and likes to collide with the player.
I've watched a lot of INP files, but I'm more than willing to hear expert players thoughts on the games they play.
Mark Longridge Twin Galaxies Emulator Judge