The difference between neuton star & black hole mass is one of the great questions in astrophysics. According to google, the most massive known neutron star [J0348-0432] weighs in at an impressive 2.0 Msun, whereas the least massive black hole [XTE J1650-500] tips the scales at 3.8 Msun. While this is not necessarily spectacular, it certainly is enough to arouse suspicion. Are gap mass degenerates just inexplicably rare within our observational stewardship, or, are we even more naïve than we suspect? Granted, achieving accurate mass measurements at interstellar distances is not always a trivial matter, but, this is akin to randomly turning up a thousand spades of dirt in your backyard only to find all worms revealed run either less than 2 grams or more than 3.8 grams in mass. It certainly appears to suggest either improbable luck, or your yard is inhabited by separate earthworm species.