Likewise, you could use it to settle 2 or 3 squares away from a river or forest and still build those improvements if you "touch" them.
In the sandbox game, you are not supposed to be able to do this. I'm not sure about whether or not you're supposed to be able to do it in the campaign, though.
I personally like snaking my cities for map control and protecting resource nodes. The faster travel thing I don't really care about - if you want to do it, fine, but I'm not going to go out of my way to make it happen.
However, I also feel that the game mechanics should be consistent between the campaign and the sandbox game. If it isn't possible in the sandbox, it shouldn't be possible in the campaign, and if it's supposed to be possible in the campaign it should also be possible in the sandbox.
Part of the argument which was raised against snaking was that it made cities "ugly" and "unrealistic" and was abusive to the AI, so they removed the ability to snake cities to forests and rivers, but it's a single-player game - if I don't like how the cities I build look, then I ought to change how I build them, and if I don't like the way AI cities look I'll raze them (or I would, if it wouldn't salt the earth on which they stood and I don't currently have whatever spell makes tiles fertile). Plus, I would hope that I'm able to restrain myself from doing something that I consider so abusive to the AI that I no longer find the game fun if I do whatever action that was.