This happens sometimes on I80 in the Winter (usually btwn Auburn and Tahoe). Snow conditions can wreak havoc on weekends. People are routed to backroads --but not everyone has chains on (so they may have to fumble and get them on while on a road without wide shoulders to pull over), or clearance that will enable to take the back roads --so they get stuck in even bigger snarl.

It's evident they (G) need to work with Traffic Engineers and not cowboy it.