Comment by bobthepanda

it is not exactly a huge secret that SDOT often would rather do weird compromises on a bike lane than inconvenience cars slightly. The NACTO guides don't really have anything on grades into turns, and the AASHTO and FHWA are notoriously not bike friendly.

This particular lane was done in 2018. https://www.seattle.gov/transportation/projects-and-programs...

You can actually see the diagram here: https://www.seattle.gov/documents/Departments/SDOT/Maintenan...

The entire reason it goes up onto the multi-use-trail to connect to Alki Trail, is because that leaves room for a right turn lane; whereas, if Seattle narrowed the two lanes to nine feet, which is a perfectly fine width on an urban street according to AASHTO, then you could have an actual protected bike lane all the way through the intersection without any sort of shallow curve.