I typically play those kinds of FMV games with my wife -- she takes notes and makes maps, while I work the controls. In the case of Fahrenheit, I think we had to do some pretty meticulous route planning, but if I recall correctly we also got lucky with the RNG, since there's a random element to where things are.
I was just starting to make sense of Supreme Warrior, at least on Easy, when I set it aside years ago, but I think the core game is unplayable on higher difficulties -- at least in a conventional sense of "playable". A lot of FMV games are only beatable on higher difficulties if you make incredibly detailed notes on Easy (where the game basically tells you what to do), and then apply them to higher difficulties (and many of those games only give an ending on Normal or Hard). Somebody on Sega-16 once described beating Scottie Pippen that way, i.e. with the aid of pages upon pages of notes.
That was more or less how it went down for me with Rebel Assault, actually. You basically can't see the enemy gun emplacements on Hard, since they're not flagged by your HUD and the video quality is so poor that they're not visible, so you just have to memorize where all of them are. It turns a decent game into an unplayable disaster.
Still, at least it's not one of those games where a character yells at you because, when you had to randomly select one of three options with no info to guide you, you picked the wrong one.
They really liked doing that kind of thing with FMV games...