So I geek-analyzed my city and here are the results.
So I saved 22 roads, but according to this thing's calculator, I've saved 24 roads because of how it's taken account of the junction roads.
If you don't get it, here's another picture to explain:
I think you are looking at road tiles incorrectly. A road tile is a connector with 4 sides. There is no such thing as a half road tile.
In Case 1, there is a straight road that each tile has just 2 available sides for production. The other 2 sides are connected with adjoining roads. Short sides on the road in a correct configuration.
In Case 2, a road end, has 3 sides to be utilized. It isn't wrong to put 2 large buildings on opposite sides and a 1 Tile productive building on the other available side, Like a Sacred Tree or a Flower Arboretum.
In Case 3, The "Correct" way has the same number of exposed sides as case 2. Your city won't suffer, bit it may not be maximum utilization.
Case 4 is case 1, but less effective as long sides are consuming space.
Case 5 takes a tile and sacrifices 1 side making it less effective. 3 of 4 sides are serving roads and not productive buildings.
Case 6 is case 1 and with short sides of building to the road.
Case 7 renders the road tile in the center of the intersection as useless for productive purposes.
I redesigned my city last night with changing the comb configuration to 3 straight roads, and 5 corners. I also have Two 2-lane roads that are separated and serve a total of 11 buildings connecting those to the town hall. Five are synthesizers needing 2-lanes. IT WAS A DISASTER. Not really. but I lost efficiency that comes with corners. A corner in a road provides a cost, and an opportunity. the cost is the inside corner will be more expensive with the size of the building. I try to put small buildings in corners to not lose effectiveness. The outside of a corner can have a large building connected with a single side of a road tile. That advantage is worth designing your city around,
I think that a city can be well designed with a single road that has effective corners accommodating large buildings on the corner connected with a single side of a road tile.
I love the work you did here. my criticism is that you should help people use corners effectively. The city design above the Roads graphic has no outside corners that can be positively exploited and the analysis of inside corners in your Tees and intersections should be addressed.