Returning a brief

I was doing a bit of research on the Bar Council Website and came across this PC type question and found the answer a little surprising.

Q. My clerk has accepted a brief for me to appear in court at a time when I am booked to be on holiday. Can I return the brief?

A. Not without the consent of your instructing solicitor. Paragraph 506(c) of the Code of Conduct states that you must not return a brief which you have accepted and for which a fixed date has been obtained or break any other professional engagement so as to enable you to attend a social or non-professional engagement. You may, of course, discuss with your instructing solicitor the possibility of him instructing somebody else.

Now it appears to me, given the above answer, that a barrister can be deemed to have 'accepted' a brief if his clerk, rightly or wrongly, accepts it on his behalf.