I agree with you,there is a lot of hot air there but I wouldn't say it's incorrect,just going into a small bit too much detail over super trivial stuff and making it seem like it makes a huge difference,some of it is true,but it is fairly one sided too. It's more a site full of facts that support his opinion and conveniently leave out the rest. Preaches his own opinion and probably doesn't even listen to anyone else,and has a load of armchair experts following him blindly and taking his word as gospel
I agree that you can have something that in theory and simulation seems perfect,gets built and tested,and either produces completely different results to the simulation,or else the same,but put it into use and it is completely unusable/unsuitable. You can put a set of lights into a car and dance around in front of it with a lux meter and take a thousand readings,and it tests perfectly,it it might actually be the wrong light for the person themselves. Imagine a chair,and it is tested by measuring the width of the seat,the length of it,the height of the back,and the angle in relation to the seat. In theory you could have built the perfect chair,everything measures up right,but in reality there is splinters sticking out of it left right and centre,it weeps sap and creaks like a mo-fo. A chair that measures up to all the requirements,but go to use it and it is a terrible experience. Same goes for anything,cakes,amplifiers,lights,photography and just about everything else.
I don't believe that if you spend a fortune on a pair of hella 4000 HID lights that you are necessarily getting 3 - 4 times the performance that you would be getting out of a relatively cheap pair. You aren't going to be driving against anyone with them on anyway.