Case review and registration: developing the review: advice from technical experts
If a contentious technical argument is likely to become a central feature of a case, you should consider the implications very carefully, preferably before you register it.
If the contentious point is not clearly covered by official guidance, you must obtain advice from HMRC’s technical experts (see TTOG1210).
Although every case is different, you do not have a free hand in developing technical arguments. You must ensure that the lines you take are within the policy and interpretation followed by HMRC as a whole.
It can be dangerous to use novel arguments without being aware of the potential effect on other cases. An argument which seems to work well in your own case could have unforeseen consequences if it was applied throughout the department. Only the technical specialists can see the whole picture, and only they are in a position to evaluate novel arguments properly.