I never really understood why you take both sides of a small branch measure both and them up and divide by 2. I get the fact that this represents the true ice accretion on a radial object like a branch but it wont match up to all the surrounding reports that the NWS/Media puts out from ASOS measurements or humans just measuring on a flat surface.
They should denote the method of measuring or just standardize it to one way only. Both of those methods are going to give you two completely different results.
For example, the ice storm we had this year. One spotter in North Haven measured 0.50 on a flat surface and i measured many tree branches that had 0.38 or so on one side and almost nothing on the other. So that means id have to take [0.38+0]/2. The result is .19 and that doesn't jive with any of the reports in my area and probably be thrown out.