This (video) is another instance where the lanes split apart but the part in the middle has absolutely no markings to indicate that you shouldn't drive there. This (photograph) is what it should look like: http://s0.geograph.org.uk/geophotos/02/24/67/2246762_3a6ea81... Is this (bad line painting) common in the US? Edit: on a second viewing, I think it actually does have some chevrons, but they're very faint.
It's pretty common to have poorly painted roads. There are definitely some roads in my area where the lane lines are no longer discernable at all if it's raining. (Newer roads have embedded reflectors.) If self-driving cars are going to survive, they need to be able to deal with the environment we have, not the utopia where all the road lines stay well painted. ;)