I get what your saying as I have read a lot of Dan's stuff and he does know what he's talking about. However, a friend of mine bought his kit from this supplier and it made me skeptical about the accuracy of the light output also. Fortunately we have a friend that has an inspection station with a lighting analyzer. we installed this kit in two of his cars, one being an old ford comet, and the other a 2008 mustang. Both were using the 4500k pure white bulbs. We did a before and after on both vehicles. there was an increase in lighting output of nearly 40% over the old incandescent bulbs in the comet and an increase of 20% over the halogens in the mustang.
That's real data that we collected because I was a nay sayer on these. Mainly because of all the reading I did on Dan's threads. Now i'm not saying Dan is wrong by any means, but this kit does show an improvement over factory lighting.