This one was named "Highway Ee" so it could've been caught with some diligent searching but wasn't.

Some legal descriptions in the area refer to the street as "NELSON B TINNIN STREET".

It was named "North B Tinn Street".

CORRECTION: The changeset summary should read "Fix up bad alignment of MO W in McDonald County, MO. "

I was thinking of a different one when writing the summary. I'll be seeing supplemental routes in my dreams...

The relation memberships were GOOD to be clear, but there was an inappropriate spur of MO W ref'd solely on the way continuing along Jesse James Road through Pineville

Also used Bing Aerial Imagery to fix a nearby road with a nonexistent connection to MO 64

Another one completely missing from TIGER

This one was completely missing.

In (2023) reality YY follows Main/Mound Street (idk what it's called) from MO 164 down to 2nd Street.

A good thing to look for with this kind of situation is the fact that TIGER had YY making a T-junction. According to TIGER YY followed Mulberry Street down to Central Street where it followed Central to the east and west...

Did not exist in TIGER at the import time.

This error stems from TIGER

It's a short state maintained route following a portion of McDaniel Street bridging Hopkins Avenue to MO 179.

This is a TIGER error.

If this is the wrong translation to OSM classification, then I'm sorry about that. This was a completely undiscovered supplemental route.

Keep this in mind when hunting for unref'd supplemental routes

Uh oh! The ways were unref'd because the W got expanded to "West"

As far as what goes in the parentheses, if anything, in the route relation names, I do not care. Even though I changed some of the parenthetical text, that was during the beginning of my edit before I fully realized that this tag is meant for human editors. As such, put town names, county names, rough route descriptions, etc.

Many of the relations had missing symbol tags, and many relations with symbol tags pointed to PNG thumbnails rather than the source SVG on Wikimedia Commons. I think I got all of them pointed to the SVGs. I also upgraded URLs to https since it was likewise an even mix of http/https.

This one's probably less important for data consumers than the MO E issue (which was problematic for OpenStreetMap Americana), but I wanted it to be consistent as well.

As for the names of these relations, I do not care what they end up being. I chose "Missouri Route XX" since that's more consistent with MoDOT (previously routes were named "Missouri Highway XX", "Missouri State Supplemental Route XX", "MO XX", "SR XX", you name it), and it nicely matches the Wikipedia article titles (one such article is "Missouri Route M (Jefferson County)"). The latter carries less weight.

I mainly just wanted nicer alphanumeric sorting in JOSM. Feel free to change it to something else. As I state in my account bio, I value consistency over any notion of correctness.

Relation #1061228 for MO E incorrectly used the "MO " prefix in its ref tag in the route relation, so I changed it to simply E.