How reliable are their clinical tests for the hairloss laser therapy

I watched the video and read the review on HairMax LaserComb – they definitely look professional and the fact that they got approved by the FDA is an upside – I don’t think they would have made it unless the clinical test they have conducted would show higher success rate and re-growth of hair in the original group in comparison with the test group.
Still I wonder about what they called – “which has been hypothesized to increase blood circulation” or “It is believed that cells treated with the HairMax convert the emitted light energy to adenosine triphosphate (ATP)”.
Those two sentences made me think twice….
Would love to get feedback about the subject…