I've been normally mapping slip lanes as '_link' highways at intersections 
since the beginning.  However, as most fellow US mappers know, they almost 
never have 'speed limits' posted for them, and that seems to help cause 
problems in some routing programs when they give those slip lanes a speed limit 
higher than the main highway.

Anyways, I've been using OSMAnd recently for occasional offline routing on my 
tablet and have come across weird routing (I'd like to call them 'bugs') at 
some intersections that have 3+ traffic lights nodes at them because of the 
roads being divided.  Here, OSMAnd routes me onto a slip lane, makes a U-Turn 
on the side road, and then continues the across the main road to accomplish 
what a simple 'left turn' could have done [1], all to avoid '1' traffic light 
node.  So, I go report the 'bug' on the OSMAnd Google group [2], and then 
somebody forwards it to the GitHub site [3].

In the response I get back on GitHub, one of the maintainers of OSMAnd says 
it's a 'map data' issue and closes it.  Claims that in the 'maneuver', since it 
avoids an extra traffic light node, it's the shortest route, even though it 
does that funky U-Turn.  Say what?!  I mean, honestly, if both MapQuest Open & 
OSMR can do that left turn 'normally' without needing to make a funky U-Turn, 
something has to be wrong in OSMAnd, right??  Sure, there isn't a 'NO U-Turn' 
sign posted for this maneuver, but still, the routing engine shouldn't be 
suggesting it since there isn't a 'NO Left Turn' relation there preventing the 
left turn from McKnight SB to Siebert EB.

So, that leads me to my question.  Does anybody think I've tagged the 
intersection incorrectly?  This is how I've been tagging intersections like 
this from since the start, and I know most other US mappers have been doing the 
same.  Or should I start adding 'false' U-Turn restrictions to prevent the 
routing bugs and then be called out as 'tagging for the router', or even maybe 
start putting traffic light nodes at the stop lines for intersections that have 
both roads divided (and just leave simple one-node intersections as-is)?

I'm very curious to see what others have to say about this to see how I'll move 
forward when I map in the future.  Also, don't hesitate to respond at the 
Google Group post or the GitHub one too as I get the e-mail notifications from 
them as well.

-James



[1] - (MapQuest routing, OSMAnd suggestion in [2] link) - 
https://www.openstreetmap.org/directions?engine=mapquest_car&route=40.53204%2C-80.01073%3B40.53002%2C-80.00614
 
[2] - https://groups.google.com/forum/#!topic/osmand/XJ-HVOHhKEM 
[3] - https://github.com/osmandapp/Osmand/issues/1501 
                                          
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