You're sure this is what Moynier and Fiddler call the "NE" couloir? Because M & F rate it class 4-5 snow and ice, but I was up there in late August and, apart from getting past the bergschrund, it was low-angle snow, in accordance with what both Croft and Secor had led be to believe. Looking at the M & F guidebook, their photo does show the line going up the N. couloir (and it agrees with their verbal description), but perhaps they're mistaken. I haven't been on the left, NE couloir, but it sounds icy, and it would make sense if M & F really meant this one and simply made an error.
Have you been on both the N and NE couloirs? Does the N. couloir really get icy? It simply doesn't seem steep enough.
I am 100% sure. Look at the picture in M&F High Sierra and they show the route up NE Couloir via the wide couloir right off the buttress that splits N and NE couloirs. This wide couloir (that I call North) DOES get ice, we encountered solid ice when descending it in mid-October 2005. When I went up this route in late July 2006, it was all snow and except for shrund it was quite easy. I agree that the 4-5 rating in M&F is overated, it is probably same or less steep than e.g. Dana Couloir.
I think Secor has this right, the wide one is North Couloir, the narrow one, which is steeper and was solid ice, is NE. Also, both M&F and Secor that first party descended this route (the wide North Couloir) on the first climb of the peak and there is no way (IMHO) that they would descend the narrow NE couloir, unless they were smoking something :-)Makes sense?