Downloaded from Speeddemosarchive: http://speeddemosarchive.com/demo.pl?MirrorsEdge_PC_SS_5732
Comments from the runner, David 'Weatherproof' Streeter: "The general tricks I used in this run:
Side-step Boost: If you are at a standstill, strafe and jump at the same time, then look in the direction of your strafe. It takes a little bit to get used to, but you'll be running full speed from a standstill if done correctly.
Wall-Run Boost: Wallrun and then jump right off, your speed will increase a bit while in the air. It doesn't seem to be affected by level loading or specific timing, making it easy to do.
Jump-Kick: When opening doors or breaking through glass, it is (usually) faster to jump in the air, then kick the door/glass open.
Wall-Run Kick: When wallrunning, kick off the wall and there will be a slight "cushion" that will reset your falling height, allowing you to descend from some falls without dying.
Fall-Break Kick: If falling in a straight line (like from out of a vent), kick before landing instead of rolling. You'll be able to start running instantly instead of waiting to finish the roll animation.
Jumping up stairs: It is faster to jump up stairs than to just run up them.
Wall-Climb: Run at a wall, climb up vertically like normal, do a sidestep in mid-air, then jump and look towards the ledge and hopefully Faith will grab the ledge. This allows you to get to high to reach places quickly.
Use Slide: Only works on PC :( If you have to use something (such as a button, or pipe), slide into it and press your Use button at exactly the right time. This will trigger the event without playing the animation, saving time. For the Use Slide, I mapped my Use key to my mousewheel. I don't have a fancy sliding mousewheel, it's just the standard one you find on most computers.
I did not use the Wall-Run Kick Jump because that is a very black-magic-like trick that rarely works. I have never had any luck getting it to work even rarely, let alone consistently. This is one of the best tricks to do in the game though so you will see segmented runs using this frequently.
I did not use the Coil Boost because it doesn't work 100% of the time, it can slow you down if not done right or the game feels like loading while you're in air or landing, and it only boosts your speed by a marginal amount. So more time was saved by not using it and focusing more on consistent running and not having my speed be reduced to zero from having botched one landing."
More info about the run at SDA: http://speeddemosarchive.com/MirrorsEdge.html