Mickey:
First I think we have to realize that modern archery is hundreds of years old, and many of the terms we used were coined hundreds of years ago. In fact the word breasted (or chested) was first written in Toxophilus in 1545 by Roger Ascham, a bow in that time would have a brace heigth (fistmele) of about 6" and the recurve was not even a part of the scene. Elmer describes breasted as the thickest (part of the shaft) at the breast and tapers both ways. Barrelled being thickest in the middle differing from the breasted type in having the swelling farther forward. Page 280 paragraph 4. In paragraph 3 he states. "One might suppoose that the narural form of a Stele (shaft) would be cylindrical throughout, but I cannot recall having ever seen an arrow of this type made by what might be called archer races of men. In fact, I think they are almost uniquely a product of modern american manufacture."
Several people on this and other sites have stated they see no difference in performance of tapered and parallel shafts. Elmer goes on to state. "Breasted arrows are very similar to barrelled. They may not be quite as stiff in the longer foreshaft but the difference is negligible. Their advantagous features is that they apparently fly with a lower trajectory than either barrelled or parallel arrows of the same weight. In some recent test at 100 yards Bill Jackson found that breasted arrows consistently grouped a half a target higher than barrelled or paralled ones, when he had used every effort to make them otherwise alike" Remember Elmer is talking target archery, which means the American or York round using 48" mats, half a target is then 24". This tells me the arrow is overcoming paradox faster creating less drag on the arrow, thus printing higher on the target.
I can hear the cries now, But I don't shoot at animals at 100 yards, no either do I but the arrow spinning on its axis at impact equates to deeper penetration.
Hope this helps, didn't mean to get on the soap box, but I want to make sure when people write articles and books they get the facts correct. There is an old saying that is so true. "When you tell an un-truth enough it eventually becomes fact"
Bob