It has always been known that GoldenEye 007 contained cheats. These are gained by finishing the single-player missions within certain time limits, and when they are turned on they allow things like All Guns and Invincibility and Invisibility. However, you can't use these cheats to get better times in the solo missions.
A few years after GoldenEye 007 was released, Push-Button Codes were discovered. By entering these complicated button sequences during a mission, you can turn on things like invincibility during a game and without tainting your score. These codes required real game time to enter, but even so, turning on Invincibility at the beginning of Caverns 00A saves enough time over the rest of the level to be well worth it.
For this precise reason, the time listed on my main "007" saved game on my copy of GoldenEye 007 - the save file with all my best scores - was 4:43. The time listed here on my times page, of course, was 6:02, which was the actual fastest non-cheating time I'd achieved. Still, I always felt that my save file was somewhat tainted by this. Given that the world record was literally three minutes faster than even my cheated time, this eventually bugged me to the point that I've now sat down and beaten it legitimately.
This was an extremely conservative route and not by any means quick by world record standards. The start of the mission was the key here. I kept my head down and zipped from left to right, beating Trevelyan to the first door. By continuing to move at top speed I was able to get all the way to the first computer console without being shot. One timed mine there, plus one timed mine next to each of the other two. Throwing the mine, I think, causes the nearby scientists to react as if you are firing at them, and run away, which means that this strategy is quite likely to destroy all three consoles without blowing up many or any scientists. I got to the next airlock leading to the spiral walkway before Trevelyan did, without having been shot either.
That was the fast bit and that much pretty much coincides with the WR strategy. The rest is much simpler. I ran past pretty much everybody (with two exceptions: the AR33 guard at the top of the spiral staircase and the first guard in the raised catwalk areas, both of whom just see you and shoot you) until I reached the semi-secret room with the many crates full of weapons and the filing cabinets concealing the secret passage. I threw a timed mine on the filing cabinets, another on the crates (for ammo) and doubled back and slaughtered half a dozen pursuing guards while waiting for the explosions. I went into the passage, threw another mine on the cabinets blocking the far end of the passage, then doubled back again to cover my back some more.
I took out the three guards in the area with the second set of pump consoles from inside the secret passage, using the AR33 sights. I ran out to retrieve the blue-hatted guard's keycard and doubled back taking out all three consoles on the way. I shot my way all the way along the lower catwalk using double ZMGs without reloading, lured the penultimate guard down the stairs (because otherwise he shoots you through the floor, which is evil) and switched back to AR33 for the final guard (collected his code card too). I used the AR33 to shoot the glass to the left, to summon the patrolling guard and the two guards (including one with the RC-P90) from the left and centre of the next room with the final set of pump consoles. I dashed in and took refuge on the left, used the AR33 to take out the second RC-P90 guard on the far side of the area, then carefully picked off the three guards (plus one grenade guard) from the central fortified area. As luck would have it I accidentally blew up the console but I was able to activate the radio and escape before being blown up myself.
Then it was just a case of playing it careful and very fast over the final run through to the finishing elevator. As luck would have it I accidentally shot a scientist, who pulled out a handgun and started shooting back at me. Having never, in all my years of GoldenEye 007, seen such behaviour before, I shot the guy dead and thankfully I was still able to get away without failing the "Minimise scientist casualties" objective. The good thing about the RC-P90 is that once the drone guns are destroyed you can just hold down the trigger for all of the final corridor.