This isn’t just a blend on the scalp issue. It’s one of those “only God knows” issues.
The fact is that we have hairs of all diameters. The electrologist treats the most noticeable hairs. Once the larger hair is gone, then we notice a smaller (diameter) hair. We all (electrologist and citizen) make observations and then develop ideas of “what is happening here.” Is it the same hair or a different hair? Hard to know for sure.
Most electrologists will agree that treating hair in anagen is best because the hair is still attached to the papilla, and not as shallow as it will be in catagen. Telogen hairs are getting ready to fall out, so the hair is no longer attached to the papilla and the root sheath is (in my observation) dried out. Will treating that catagen or telogen hair result in the hair growing back? Hard to know for sure.
All hair is in a constant state of growing and shedding. One hair is difficult to track - since there are at least a million of them. Hard to know for sure.
Did I even come close to answer your question? Hard to know for sure. grin