[Intrepid Homoludens]

In realMyst it was done in such a way that you, the player, could not move around the room with the FMV character in front of you. If you could move you'll realize he was a flat image, and that will f#&k up the immersion (he's not supposed to be some holograph, but the 'real' guy in the same room with you). That the game forced you to more or less stand still while watching a flat FMV character talk to you already screwed up the immersion.

It has be a HUGE amount of unnecessary work to make it so that an FMV character can walk as a 3D character in a 3D world while you are walking in that world at the same time. Might as well toss that dumb idea out and just use 3D characters in game. As it stands, some of those detractors developed unrealistic expectations as to how technology works today.