In regard to queries about what Nalbandian has ever done with his backhand, the most appropriate answer is probably "not much", especially compared to most of the other notables on the list. But this, I think, doesn't indicate that his backhand doesn't belong on the list. For one, a list that is top-heavy with players who possess super-consistent backhands but weren't known for their shotmaking is no more accurate than it is biased (in favour of consistency). We all know Nalbandian isn't the most consistent player on the list, and although his lack of consistency should probably be attributed more to issues with fitness, temperment and mental strength than to his backhand (which is probably the most reliable aspect of his game), I will admit that his backhand is not as consistent as many others' on the list. This being said, the shotmaking off his backhand is the most consistently brilliant I have ever witnessed. Not a match will go by that he hasn't hit at least a dozen absurdly angled, out of nowhere, backhand winners. The ease and quality of his shotmaking is astounding. So while he doesn't have a neatly balanced backhand that is near equal in terms of its reliability and its shotmaking potential, he still has a backhand that, when the two components are average, ranks very high on the list of all time best.
As to the purported need to have achieved something huge to be said to be one of the best ever in a particular aspect - I find this an unreasonable requirement. Do we really want to exclude, for example, Ivo Karlovic, from being near the top of the list for best serves ever. His serve simply is one of the best of all time. The guy can barely play tennis from the baseline at all and yet manages hold percentages, year in year out, that are comparable to the best players in the game, hits more aces than anyone, and surely more unreturnables. Roddick, himself an all time great server, said that his own serve couldn't be compared to Karlovic's - that Karlovic's was "the biggest weapon in tennis".
What does all this have to do with Nalbandian's backhand? Well, the situations are analogous...don't rule out Nalbandian's backhand being the best just because he hasn't won a major or two, instead, go and watch him hit it.
