Interesting video. I don't doubt that the product is an effective garment for dealing with hot temperatures. However, the gent's assertion that mesh gear is not a good solution to the problem is not backed up with any evidence. In fact, the video does not compare LD to mesh at all. The key to cooling is evaporation. A zillion years of evolution has given us this temperature regulation mechanism. It works with a cotton shirt or any number of the new technical fabrics. In the end, it comes down to stopping for wetting anew your undershirt. I wear a mesh riding suit and in the summer I experience dry temperatures approaching 100 degrees. My mesh suit allows me to do this, so long as I make sure evaporation is taking place. I think it is a bit of a stretch to argue that the Bedouins cover up in the desert, so riding in a mesh suit is a no no. The comparison is not cover up as opposed to ride naked. You are covered with a mesh riding suit!
I'll say again that I have no doubt LD Comfort garments are effective. But there are other viable options.