No, honestly I don't see how it gives more credence to natural seletion. Giraffes don't know how their laryngeal pathway is laid out so how could they select one another by means of it.
Natural selection is an environmental pressure, not the intention of the organism. And because the pathway of the nerve doesn't influence there appearence, it wouldn't have any reason to play a role in sexual selection.
Why shouldn't a laryngeal pathway go near the heart?
If you look at the nerve's pathway you'll see how uneconomical it is, and why it gives credence to it's formation being natural process rather than directed process.
If there is no reason for it to be there would not have natural selection bred it out of existance?
Short answer; Because the accumulation of variations is such a gradual process, the 'detour' developed in incremental stages - but it obviously wasn't an impediment to survival. From a 'design' perspective ie. creationsim, it's uneconomical - but it makes sense if it developed via natural selection.
From personal experience, in order to understand how natural selection can produce complexity it's best to read a systematic presentation of the theory of evolution. I recommend; the greatest show on earth by Richard Dawkins.
I have seen sceince change it's thought about things it was way to sure about. There are many outstanding sceince developements. However there are many that are like a two edged sword because of the short sightedness of humans
Here's the best answer to that;http://www.youtube.com/watch?v=TgzbUuLMuBM
I'm simply asking you to look at the evidence for the theory of evolution, alongside the evidence for christian creationism, and then form a conclusion regarding which one you think is most likely.
I can't think of a situation where the length of the laryneal nerve pathway of a giraffe is going to matter one way or the other to me. However if you can point out way it might be important I'm willing to give it some thought.
The bigger picture is; design vs natural processes.