Prince of Dzun
Intrigued by your posts about George Welch potentially breaking the sound barrier before Chuck Yeager I got my hands on the book "Aces Wild" by Al Blackburn, which seems to be the main source of this story.
The book is written in a style which does not inspire confidence in its historical accuracy: for example extensive "conversations" between leading players in the story are quoted extensively in a verbatim fashion, when the author is obviously making them up based upon what he imagines was said. Throughout the book the author demonstrates a clear bias towards the work of North American Aviation (who he once worked for) and this seems to cloud his judgement of historical sources.
Despite the hyperbole on the dustjacket, the book does not actually contain any evidence that Welch flew through the sound barrier before Yeager, other than pure hearsay. Indeed, the people that Blackburn actually bothered to speak to told him that Welch did not do it.
It does seem clear from the book that Welch actually went through the sound barrier several months before he "officially" did, but he did it after Yeager.
I think a lot of people (including Blackburn) would like Yeager to have been second because they don't like Yeager's personality style, but on the evidence of this book I don't believe it happened.