I got a feeling that with the CMH that's part of the issues, there seems to be a lot of difference between reflected ambient light and light coming straight off the source, there's a big intensity difference. Reflected light's probably better when it's concentrated to some degree and the intensity is sufficient.
When I was running CMH, i used to run 2 1000w DE units@1200w each, I would have probably been better off running a bunch of 400 watt units in an array instead, allowing for more spread, while lowering the unit further into the canopy, net gain in free intensity.
ie. the sun puts out more light than a distant supernova. These are were efficiency is greatly realized.
I notice a big difference between my Spyder type unit vs the Quantums, even with the same basic Samsung 301H diodes, spread out is way more efficient, and it can be dialed closer into a more spread out area, further increasing the gains. Then intensity can be further manipulated with the dial. for example, I'm at full strength on the quantum @4 foot, but I'm at 33% full power @ 2 foot with the spyder, with double the area at lower power.
Note the t5 I use in the background to supplement UV from the A-B spectrum, during flowering to increase terpenoid production and THC content/quality/complexity. aka "suntanning the plant with beneficial stressors."
Indeed, certain strains could become highly individualized with very specific lighting spectrum regimes, altering chemical profiles of oil/terpene content, and complexity. Trade secrets are likely to become obstacles to further progress, it's already happening. People don't want to give away their "edge"
