Here is Christopher Hinton, U.K. reactor pioneer, exhibiting his robust ego to his boss at the beginning of 1955:

Dear Edwin, I have been thinking about the proposal that I should give a lecture to the World Power Conference at their meeting in Vienna. I am, if necessary, prepared to do this and I am not in the least funking going to Vienna. It does seem to me, however, that it may be a foolish and unnecessary risk for a man occupying such a key position in Atomic Energy to go so far behind the Iron Curtain. My feeling is in favour of sending Gott to give this lecture. He is technically competent to do it, but does not occupy a sufficiently exalted position to merit undesirable attention. Can you let me know what you think about it please. Yours sincerely.

Hinton, Christopher. 1955. Hinton to Plowden, Jan. 28, 1955. AB 19/13. National Archives, Kew, United Kingdom
Christopher Hinto memo