What is the difference between a dotted line and a solid line? Good question. The Vehicle Code doesn't mention a difference unless it is two parallel white lines.
I can't seem to find your point in making a distinction between "direct you where to drive" and "merging in an orderly fashion". Two ways of saying the same thing to me, perhaps you could expand on the thought.
I, too, have driven in darn near every state in the union. And, as you said, there seems to be a general consensus that the white line is not to be crossed. I think that is good. It is there to "assist with merging" or for whatever reason it is there. And if people think they cannot cross the line, so much the better. However, my point was not that "people" believe that the line cannot be crossed, I was pointing out that there does not seen to be a Vehicle Code section that addresses that specific item. I was hoping someone could research the issue and correct me, assuming I am incorrect.
We could fill a board discussing all of the myths around traffic laws. I once had an instructor that told a story about a trip he had made downtown to the doctor. The trip included many anecdotal comments about things he had done on his way. For instance, needing to check directions, he pulled to the curb in front of a fire hydrant and parking there. No red on the curb, just the hydrant. He never got out of his car and stayed there about 5 minutes. Then, after checking behind him for traffic and finding no one else on the street, he pulled out into the street without signaling.
Some of you, and most of the class considered that activity to be in violation of two vehicle code sections when in fact there was no violation.
Funny what we think the law is versus what it truly is.
BTW - I really hate to give up the BMW. But my Shrine group only allows Harley Ultras in the group when we ride in parades. I can't justify having two full dress bikes in the garage, although they seem to get along just great.