--is that the laser (and even the LED's if monochromatic and strong enough) may be able to affect the nitric oxide pathways and promote microcirculation, which is supportive of nerve function (and a lot of things, besides).

The mechanism is many small fiber neuropathies, such as those associated with diabetes or some anti-nuclear antibody autoimmunities, is thought to be primarily ischemic or circulatory; the primary breakdown is in the small blood vessels, which then do not bring enough nutrients/oxygen or get rid of waste products as efficiently, and this leads to nerve starvation/breakdown. So anything that promotes better inflow/outflow is likely a good thing.