One more option would be a flag in the elevated way/bridges whether stuff beneath it should be cut.
I think this is a great idea because it'll enable the use of elevated ways as additional eye candies, and because it almost saves the current flexible system of drawings about trees and houses.
it becomes a somewhat 'official' way to go, and chances for actual secondary wayobjects would slim down.
I don't think so because there are already addons which enable us uses not expected at first, and none of them is supported as an 'official' way to go.
cause problems when you try to place a signal on the track (you might hit the elevated way instead)
I've known about it, so I've planned how to 'divide' elements to objects, and finally I found a well-diving way not to cause such a problem. Basically, what should be placed back will be put lower, and the fronts will be upper.
invite to all kinds of floating vehicles (don't say players won't do it, I've seen too many trains on my borderposts to believe that)
You wrote "don't say players won't do it," but I can say players won't do it with assurance.
There are already many addons which use ways to another purpose.
For example: piers under elevated ways, pedestrian-way, floor of plazas, truss bridge's stiffener, pipeline, etc...
Yet there are so many, I haven't heard of inviting vehicles accidentally, so I can say that additional eye candy doesn't bring accidental inviting, either.
don't work with tunnels
Actually, I think one wayobj is enough to tunnel ways because overhead wire's pillars aren't needed there.
If you want in tunnels too, you can build additional way over it, since it might take some effort.
disable bridging over them
So I wrote this.
if I set 'height_conversion_factor = 1' and assume two layers as a layer, I should be able to put twice as many objects on one way as before, without losing any functions!
You might not know it, pak128's default is 'height_conversion_factor = 2.'
So if I set 'height_conversion_factor = 1' and use additional elevated way, we can bridge them same as before.
With the current setting, bridges can be built over 2 or more layers higher than lower way, because of 'height_conversion_factor = 2.'
And this condition will not change because bridges must be higher than additional way, which is higher than normal way, but 'height_conversion_factor = 1' is set.
Thus, to me, Leartin's idea has no problem, contrary to what Leartin insisted.
Following the One-way patch a secondary way-obj is almost on the road-map, or basically an 'overtake-obj'. Seems like the best solution for that patch.
(The problem is maybe that my English skill is weak.)
The first half of the quotation seems to suggest that we bring that discussion's idea to this discussion.
But the last half clearly suggest the reverse thing.
Which does it mean?