To clarify, tint lower than a certain percentage that prevents me from easily seeing the driver is what I'm referring to. I use any and all cues from other drivers to determine their intentions when I'm on the road on a bike or driving a car. Being able to see the driver so I can tell if they have seen me or are at least looking in my direction at intersections is something I rely on. I would have used that information when approaching that intersection if I was in the saddle instead of Joey and wouldn't be surprised if he uses cues like that as well. I'm not sure what I'd consider an acceptable percentage as even light tints have a great effect at night.

Anything that makes cars or their drivers less visible is a terrible idea. Stupid things light brake light covers, especially tinted ones. Hell, even taillight clusters that don't have orange turn signals suck, imo.