Thread: Chamber Reamers: Straight Neck or Tapered Neck

A question for the technically inclined here please.

What are the perceived trade-offs of having the above; a chamber where the neck is cut perfectly cylindrically versus one that tapers down in diameter from the shoulder neck junction out to the case mouth by say 0.0005" - 0.0015" (as this appears to be the common level of narrowing)?

Given how the straight wall design appears to predominate, and the springiness of brass, I can't see the taper being just a design choice around ease of extraction.
Surely the designers have other benefits in mind?
Maybe the idea is that sizing a slightly conical neck results in improved centering - particularly in a bushing die situation where the case walls may not necessarily be contacted - with better resulting concentricity in the sized neck?