my 2 cents...
On the road, probably not. As a roof about 5-7 meter above the road (15-20 feet?) maybe.
on road : problem related to changing the surface friction, reflections (they cover that at around 1:20 in the video) if certain cells get broken they'd be hard to replace without interrupting traffic, issues with ice/snow during winter, with salt and whatever is used to prevent ice, issues with paint for road signs on the cells bla blah
as a roof ... on one hand lower visibility for the drivers during the day, but on the other hand drivers won't have the sun in their eyes anymore. less rain, ice whatever on the road ... theoretically, because actually covering the road may get the roads colder during the winters as whatever sun is there no longer heats them during the day.
Lack of light may be a non issue if small spaces are left between solar cells at certain intervals or if there's some led lightning used on the bottom of the solar cells.
broken panels could be easily replaced and cleaned using simple cranes by the side of the roads