[OSM-newbies] Question about how to connection correctly highway links

[Sebastian Arcus]

I have a question about how to correctly trace highway links at 
junctions/intersections. Sometimes a link physically crosses over one or 
two other lanes coming from the other direction of traffic, before 
reaching the lane it is suppose to merge into. Now, these junction 
points do exist in real life, but from the point of view of navigation 
software, they are useless as one is not allowed to turn turn into any 
of those lanes of traffic it crosses until it reaches the right lane it 
is supposed to merge into.

My question is, should these junction/common points between paths 
actually exist in OSM? Wouldn't it be better to draw the highway link 
like it wouldn't actually intersect with those oncoming traffic lanes - 
and just joined it to the final destination lane? I use Navit GPS - and 
it sometimes assume I can turn into those oncoming traffic lanes just 
because the common waypoint indicates there is a joint. Maybe other GPS 
navigation software does the same mistake?

In case my explanation is a bit fuzzy, I will give an example. The 
following relatively simple junction is in Liverpool:

http://www.openstreetmap.org/?lat=53.394271&lon=-2.982713&zoom=18

Imagine you are traveling northwards on Sefton Street towards the 
junction. The right-most link (looking northwards, in the direction of 
travel) is obviously a no-no as it is a one-way going south. However, 
Navit suggested for some strange reason that I take the middle link, and 
then turn immediately left on the first lane of traffic that the link 
hits into Chaloner St and continue northward. In real life, that is 
impossible, because that particular highway link (the middle one) is 
only for crossing over the first two lanes of traffic it encounters, and 
then merging with the far most one and continuing east on Parliament Street.

My thinking was that if the middle link coming from Sefton Street didn't 
have common waypoints/joints with the first two lanes, the navigation 
software would have never had any reason to suggest such a move. Those 
points are as good as non-existent in practice, as they can't be used 
for turning left or right into those two lanes.

Could anybody with more experience weigh in on this with some pro's or 
con's please.

Thanks,

Sebastian