After looking around it seems there is no consensus on reading comets. I've seen some analysis that consider all aspects in chart throughout the visible range. However, the message of the comet is only understood well in retrospect. It seems difficult to tell whether it will be malefic or benefic when trying predict the future. There does appear to be a leaning toward the idea that all bodies associated with the oort cloud are malefic in some way, but it doesn't seem likely to me.
The most sensible approach is to apply the perihelion as a sensitive point that can remain active for a time period, similar to an eclipse. Keep an eye on activators crossing this point, such mercury, venus, and mars. IN this way it is more of a timing indicator.
While eclipses are connected to the cycles of life, new comets forced out of the oort cloud are like urgent messages sent directly from the master of the universe. It' kind of nice to have some evidence that we might not be left for dead in the universe that functions as an autonomous machine. Instead of yods, maybe comets should be called the Finger of God.