I always see those solutions. But they are not good one, I mean they are kind of a hack and require so specifique thing to work.
One of the main thing is, great you can os poles that you later destroy to place floating belts. But what if something is already where I would need to place the pole? Should I have to destroy it to put the pole then the belt and then the thing that was previously in the way? But wait what if the thing that bloked the way also required some scaffolding to be built where I want it? Oh and bad luck, that scaffolding as to go were the belt I wanted to build at first is. Well I'm kind of stuck, one hour into it, destroyed half of my factory and find it won't work.
So I hope people can see that it is bad design to offer solution through the need of building then breaking.
One possible solution : allow people to place naked/floating belt by latting them chose it's horizontal position and vertical position through intelligent control without requiering he need for scaffolding. I don't see why it wouldn't be possible since you could obtain the same "unrealistic" floating belt by other mean.
This is one example where the building system needs a lot of work to feel good.