Watching this video from Karl Jobst, he mentions that the speedruns of several Doom ports must take into account the game's poor frame rate. I know the 007 Goldeneye speedrun on the N64 also involves keeping the frame rate as high as possible. I assume many other games have similar problems.
But I don't understand why frame rate matters in these two games, because they use in-game timers for their timing. I would think if the frame rate dipped, it would slow the timer down just as much. What's going on here?