I agree, as far as how and why they do it. There just seems to be a lack of learning on their end. You would think after 10 plus years, we would see something different. Yet we still get the same absorbion data McCree pretty much came up with 40 years ago. They can and do spend a lot of money, yet nothing seems to change in their findings. Unless you think the manufacturers lie on the data sheets, more testing of the same nature is pretty much useless.
The only thing I see from it is more douche bags that citing shit they read, but have never grown a plant. One look at the diy led thread will tell you there's 100 dip shits citing led efficiency or photosynthetic efficiency for every 10 that have actually taken crop to harvest with more than one light.
But it's a free country right? So instead we spend weeks sifting through 300 pages of bs to get to about 10 pages worth of good info.