I’m sorry but as 4th year botanical science student with the intentions of specialising in plant and cell physiology, I would have to completely disagree with the comments made by you and the "Hortilux guy"
It has been scientifically proven that, plants have to down-convert blue photons to a lower (red) energy level to efficiently use them in photosynthesis = (wasted heat energy). Blue photons do have one very important roll though, and that is they inhibit auxin synthesis. This is advantageous because it creates stockier shorter plants with more bud sites during the vegetation period in angiosperms.
PSI and PSII photosynthesis pathways require two photons, 680nm and 700nm. It doesn’t need to be specific to these wavelengths but the closer it is the less energy the plant has to waste in conversion.
The Hortilux guy also directly implied that LED can only be successful in hobby growing where you’re growing a shorter plant, and is not viable in commercial lighting. So what he is basically saying is LED has no "penetration" which is a complete bullshit implication, photon density is photon density regardless from what light source it is being emitted from. It is just as useful as any other lighting source in commercial applications. High Quality LED lighting has the ability to be the most efficient lighting source on earth period.
Green is also important as it aids in the absorption of other wavelengths in photosynthesis as well as the photomorphogenic aspects, but I won’t get into that as it gets rather lengthy.
He also implies measuring photon density in watts per square foot, which is completely stupid and rudimentary . Is PPFD the best possible measurement no, but it sure as hell beats watts per square foot.
How GreenGenes contained himself and didn't rip this guy apart, I don’t know. He sure has the capability, knowledge and intelligence to do so.