OK, play that same situation against the mountain rules for survivability. You would have already pre-passed the cars on the double yellow one at at time already and would have been in front of them already.
They would have been very durn well aware of you and that you wanted to pass them a long time ago if you had been eating their asses one by one as per the mountain rules.
If that cager had pulled over to turn left in the instant you were passing them , you'd have been hit anyway.
There is no real protection against active cager stupidity such as you describe.
However, if you saw them start to move over you could have hit over to the left hand shoulder as you would be going say 15-20 mph faster than them at that point in time you would have likely cleared them.
The odds of them pulling over into you with your engine going at full song and with them seeing you coming on up the line of cars would have been much much less
*.
You see, they would still have had to slow down to make that acute left angle turn to make the driveway, so you would have been able to swerve over and still move ahead of them with your plus speed at that critical point in time. Plus they would HAVE to be seeing you by then as they would be steering their bumping into you ....
Cagers are dangerous -- the only safe place for a cager is BEHIND you.You can avoid a lot of things by intentionally taking to the shoulder. Or the gravel road, or the median, or like Lancer, splitting the lanes between the oncoming cars. Better to do that than try to combat a ton and a half of cager steel. Or, if you have to, throw the bike down into the loose gravel and dance away from that big assed front bumper of the F150 Ford truck on foot, it is
much better to abandon the bike than to go under the F150's tires with your bike .....
all real examples are from the last mountain trip and from previous mountain trips .....*Unless it was done on purpose, and I have seen shite like that done on real roads with real cager drivers. Road rage is real, and getting stuck behind a slow trailer is likely to bring that rage out some when the bikes start dancing on past. I have seen a cager open a car door on a bike that was splitting lanes because the cager couldn't move and the bike could -- road rage is senseless when it happens.