PS: Some may say that I have hubris to even question Usener or Bailey or even DeWitt, and maybe that's true. I would defend myself by saying that I'm not questioning Usener, Bailey, etc al. on a whim. I find a troubling number of their citations lacking in relevance to their assertions.
You're not alone, Don . I think DeWitt's book is a good introductory book that can spark the interest in Epicureanism in people. At least that seems to be the idea behind the book and Dewitt accomplished what he aimed for. However, when someone invests any time in the study of Epicureanism, it becomes very clear very quickly that DeWitt wrote his book not as a scholar but more as an enthusiast [originally I used word 'fanboy' which may suggest derogatory intentions which is not what I intended - TauPhi] of Epicurus. With all due respect to his work, he doesn't seem to have problems drawing conclusions out of thin air to make Epicureanism what he wants Epicureanism to be instead of presenting it for what it was, to the best of available resources.
As far as Bailey and Usener are concerned, their work is not perfect either but I'm very grateful for the amount of work they put in their research and publications.
One way or the other, it's great all these people decided to pursue their interests and now we can benefit from their beautiful, imperfect work and try to make more sense where possible by making our own mistakes on the way. Hubris or no hubris, studying stuff is so much fun, isn't it?