You're right about it being one roadway, but it's like this for routing reasons. Since Gryphons Walk has two one-way segments connecting into this intersection, the map has to show that: 
- you can get into Gryphons Walk by turning right from 23rd WB or turning left from 23rd EB
- you can get out of Gryphons Walk by turning right onto 23rd WB or turning left onto 23rd EB -- or driving straight into Quincy Drive.

I would guess that it is fine to keep it the way it is right now (unless you have new information from on-the-ground, of course.)