"Also be aware that you would have to be in front of the plane and on the flight path to actually get it to shine into the pilot's eyes. From below and/or to the side, the best you would get was to illuminate the roof of the pilots cabin, and from behind you could not shine it in the cabin at all."
Yes, the light does have to get to the cabin for it to be an issue, true. But particularly in small planes, the windows are a type of plexiglass which have a tendency to distort the view, particularly from collimated (or nearly-collimated) light (picture how looking top-down through water has a tendency to distort things). Simply having part of the light hit the window will have both a scattering and bending effect on the light, so you would only need to get "close enough" for the light to affect the pilot's night vision. This is exactly what happened to me.
Let's also get one thing straight, that when these incidents happen, it's clearly a deliberate act. I slightly deviated my flight path to try and locate the source on the ground (didn't have time to circle the area), and I could clearly see the shaft of light coming from the ground specifically searching the sky to illuminate my plane. The aiming motions of the light were not random. Any deliberate action to impair the capabilities of a pilot deserves criminal punishment. Sure, 14 years for *only* shining a laser at a plane is a bit excessive (unless it actually caused a crash or caused multiple injuries), but from someone with a history of not following the law, it sounds appropriate.