This is an amusing and useful quote from Judge Kevin Poole in the case of Agar Ltd v HMRC in 2011. The case related to penalties imposed by HMRC for late payment of PAYE, but it could just as well have been any other area of tax.
“...we note that HMRC’s manuals may give an indication of their view of the law, but they are not always correct. Indeed on a number of occasions they have been found to be wrong. We do not consider manuals to give an authoritative guide to the meaning of legislation.”
Neither do we!