They aren't that different at the surface though - same with the ICON (and probably the Euro once it comes out). The GFS tucks the low in closer to land (in fact over land) and ramps up earlier. The CMC is 15 mb weaker at 90 hr, and 100 miles SE of the GFS. By hour 102 the CMC is about 5 mb stronger and maybe 75 miles or less apart. Its just the timing that makes the difference. Similar with the ICON. By the time they really ramp up, they are south of Maine. Its just that those differences of 12 hours in when the various parts that will make this system bomb out come together are super meaningful to weather we see a historic blizzard or nothing.