The sun's rays lose intensity with distance according to the laws of physics (inverse square law). They don't originate from your window they originate from the sun so the difference in intensity from the sun to your window compared intensity from the sun to your window PLUS 1 meter is not perceivable. He says later on that with modern LED and HPS you don't need to have them close (which you probably didn't see)
With so many posts you shouldn't be spouting this nonsense all you need is a PAR meter and a light and you will see that moving the light higher lowers the light reaching the canopy. With your logic i could hang my lamps 2 meters above the canopy with no negatives.
And "this bafoon" is Robert Pavlis is a well-known speaker, and educator with over 40 years of gardening experience. He is the author of Building Natural Ponds, and publishes the popular gardening blogs; GardenMyths.com and GardenFundamentals.com. As the owner and head gardener of Aspen Grove Gardens, a six-acre botanical garden, he grows 3,000 varieties of plants.
1 get a decent light
2 remove heat mat
3 get a fan
4 watch P levels
sound advice