In many cases, regardless of what I personally believe a road "should" be classified as, I'm willing to accept the NFC standard as applied by MDOT simply for the sake of having a standard. Even having something listed in the Wiki still leaves open a lot to subjectivity and local interpretation. With the NFC, however, it's hard to argue with how MDOT and the various county road commissions have agreed to classify roads. Red is red and yellow is yellow. There's no relativity allowed.
points out, traffic counts play a big role in the road classification, but there are also a number of other factors. Counts can show how a road is currently used whether it is two lanes or eight lanes, divided or undivided. Commute patterns have evolved over the past few decades from primarily flowing from the suburbs into downtown Detroit to flowing from suburb to suburb. This creates a huge criss-cross of actual traffic volume that the existing road structure was initially not designed for.
In other cases, MDOT would consider something a principal arterial not only because of current flows but attempting to gauge (and even direct) future flows. Maintainability is another concern. Where there may be 20,000 cars per day on a 30mph two lane stretch, it may be worth it to keep it a smaller road in order to cut down on maintenance costs of a four lane or larger road, for example.
I want to quickly look at the Maple Rd example, and another for Pontiac Trail. One little segment of Maple just east of Drake Rd had a vehicle count of 26,033 on 9/17/2012 with an Annual Average Daily Traffic (AADT) count calculated at 25,360 for 2012. That's quite a flow for a two lane stretch in a residential area. https://www.waze.com/editor/?zoom=6&lat ... 91&env=usa
Pontiac Trail drops down to 30mph right at Walled Lake coming from the Novi area, and it has a nice, small town feel at that point. That doesn't mean that it's not the best local artery, and it didn't stop 17,398 vehicles from taking that route on 6/13/2013 with an AADT of 14,740. Btw, that's down from an AADT of 19,802 in 1998... https://www.waze.com/editor/?zoom=5&lat ... 74&env=usa
By comparison, SB Telegraph had an AADT of 27,080 and NB Telegraph has 37,570 at the intersection with Maple. Woodward had an AADT of 28,490. Does that make Maple Rd pink on the NFC map? All this does is throw some data at a debate where, for better or for worse, someone(s) at MDOT decided to apply NFC and considered them all principal arteries. Through all of the smoke and mirrors, Maple Rd was deemed the primary route from Walled Lake to Birmingham. He probably should have consulted the Waze forums first before making these judgments
Here is the link to Oakland's traffic counts, which is fascinating: http://oakland.ms2soft.com/tcds/tsearch ... kland&mod=
I don't want to get into too many specific examples, but to anyone who provides examples saying [x] road should be [y] road type, or [x] would never
be a minor highway because of [z] conditions; we could argue forever. In most cases, I would probably agree with the person. As Riamus
points out though, we need to think in terms of what the road is used for rather than how it may look on certain or even on all
stretches. It takes humility in many cases to stay above the fray and ignore what "my" classification is and realize that at the heart of it all, we're adopting a system that was designed for better routing. This is not to get one person from point A to B the way that I think best to do it, but to get tens of thousands of people from A,B,C, and D to any combination of X,Y, and Z. In that case, let's leave it to the pros that actually study traffic for a living and adopted and applied the NFC classification. Drive the routes in question with navigation on. NFC works well with how Waze routes and is much better at finding alternative routes.
One quick point as well about speed limits. Speed limit does not dictate road type, and the potential
inclusion of speed limit into Waze is a very contentious point. That is a separate discussion. In most cases, road conditions, number of access points, etc. dictate a safe speed limit. The speed limit doesn't not necessarily dictate whether or not I should choose the road. Just to consider, Michigan Ave/US-12 may drop down to 30mph in stretches like Ypsilanti or 40mph through Wayne, but would we change it to Primary Street for those segments only to pick up again as a Major Highway once it climbs back to 50 or 55mph? How it looks doesn't change what it is. It's still the "artery" it always is even in the slower segments with fewer lanes and more stoplights. For a separate, unrelated discussion on speed limits, for anyone who hasn't seen the following thread, it is worth reading:https://www.waze.com/forum/viewtopic.ph ... peed+limit
At the end of the day, I would rather defer to the authority on traffic in the area--even if I don't agree with how every segment is classified. In my opinion, it beats having a patchwork map that routes differently every few weeks based on the most recent editor's interpretation of the Wiki.