How to be Insulting about Incompetence

To an orchestral player:

'We cannot expect you to be with us all the time, but perhaps you would be kind enough to keep in touch now and again.' — Sir Thomas Beecham

Noel Coward once described a director with whom he had worked as a young man thus:

'He directed rehearsals with the airy deftness of a rheumatic deacon producing Macbeth for a church social.'