A butterfly on a wheel?

IN READERS' FORUM Taxation 17 November 2005 a query 'Business add back' requested advice where a client had purchased a property comprising business and private premises (plus goodwill etc.). A mortgage for less than the cost of the assets forming the business element had been obtained and the interest claimed in the business accounts. HMRC had disallowed a proportion of the mortgage interest as relating to private rather than business purposes on the basis that the interest was not incurred 'wholly and exclusively for the purposes of the trade' under ITTOIA 2005 s 34 (TA 1988 s 74(1)(a) (as was).
Two replies took alternative views as to whether the interest was allowable and the Taxation website (www.taxation.co.uk) has some additional ones.
Hot on the heels of that question has come the Special Commissioner's decision in I Dixon SpC...