I agree with Bookworm - "left hand circuits" makes far more sense.
I disagree about not saying "left hand circuits", thoguh - it depends on the circumstances. For example, at the airport I fly from, the circuit on all the westerly runways are generally right-hand. But there are sometimes very good reasons (the police helicoptor operating in the vicinity being a common one) why this needs to be changed to left-hand, and on these occassions it's important that "left hand circuits" be stated by ATC and read back by the pilot? Just one example of many - there are so many cases that CAP413 can't possibly deal with them all, but must give examples which are generic enough that a bit of common sense will fill in the gaps.
FFF
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(PS - for anyone who reads the first post and doesn't know what the fuss is all about - I doubt there are any instructors in that category but this forum is read by people other than instructors - the phrase "take off" is only ever used on R/T when you are cleared for take-off, so there can be no confusion about whether a call is a clearance or not)