The very first thing that wikipedia says about jury nullification paints it as much more than "an unfortunate edge case":
A jury verdict contrary to the letter of the law pertains only to the particular case before it; however, if a pattern of acquittals develops [...] it can have the de facto effect of invalidating the statute. A pattern of jury nullification may indicate public opposition to an unwanted legislative enactment.
Wikipedia and cynicalkane aren't conflicting. cynicalkane is making a claim about why nullification exists. (It is impossible to prohibit nullification without also giving courts the power to ignore jury decisions based on what they think is in the jurors' heads.) Wikipedia is making a claim about the effect of nullification. (Nullification can effectively repeal laws, a very powerful consequence.)
A jury verdict contrary to the letter of the law pertains only to the particular case before it; however, if a pattern of acquittals develops [...] it can have the de facto effect of invalidating the statute. A pattern of jury nullification may indicate public opposition to an unwanted legislative enactment.