Just followed this for my new sled that I built over the weekend. My first guessimate was out by 0.2mm over 1.5 m of cut but after adjustment is was only out by 0.05 mm. I think I can live with that!
The only thing I might recommend is to repeat the cut a couple of times before changing anything so you can work out the error (ie a bit of sawdust getting in the way etc). You don't really waste any more wood doing this as you can just take a thin shaving off all the sides but the last one.
Joking aside, it is something that I have to take into account during my day job. I image human cells on a microscope and when estates and buildings decide to turn on the air conditioning the cells that were perfectly in focus slowly drift away (human cells are about 10 microns deep and the hunk of metal that is the microscope will expand/shrink about 1-2 micron for every degree oC). It can get really annoying!
That's basically the same system that Festool recommend for squaring the cross cut slide on their Multi Function Table. But what this guy does better is explain how to translate the error measurement into corrective action.