“on the assumption that the price be diminished by the extent to which the value of the house and premises has been increased by any improvement carried out by the tenant or his predecessors in title at their own expense.”
“(1) The extent of the fiction created by a deeming provision is primarily a matter of construction of the statute in which it appears. (2) For that purpose the court should ascertain, if it can, the purposes for which and the persons between whom the statutory fiction is to be resorted to, and then apply the deeming provision that far, but not where it would produce effects clearly outside those purposes. (3) But those purposes may be difficult to ascertain, and Parliament may not find it easy to prescribe with precision the intended limits of the artificial assumption which the deeming provision requires to be made. (4) A deeming provision should not be applied so far as to produce unjust, absurd or anomalous results, unless the court is compelled to do so by clear language. (5) But the court should not shrink from applying the fiction created by the deeming provision to the consequences which would inevitably flow from the fiction being real. As Lord Asquith memorably put it in East End Dwellings Co Ltd v Finsbury Borough Council[1952] AC 109 , 133: “The statute says that you must imagine a certain state of affairs; it does not say that having done so, you must cause or permit your imagination to boggle when it comes to the inevitable corollaries of that state of affairs.”
“What assumption (d) requires is a calculation of the amount of the increase in value caused by the improvements. That necessarily involves a valuation of the property as it would have been on the valuation date if it had not been improved. Before the Lands Tribunal both valuers agreed that any potential for improvement would be included in the achieved sale prices of unimproved properties; in other words, that a valuation of an unimproved house and premises would include the value of any such potential. It follows that an increase in value caused by an actual improvement must be calculated as an excess over the unimproved valuation (including the value of the potential for improvement), notwithstanding that the potential is merged in or absorbed by the actual improvement.”
“In this case my view is that the reality principle tells us no more about the Withdrawal Assumption than is gathered from its wording, as interpreted in accordance with established principles. The reality principle is only saying that departure from the real world must be no greater than is required by the statutory Withdrawal Assumption. If you are not required by statute to depart from reality, you must stick with reality. But the principle does not determine or limit what the statute commands us to assume contrary to reality. The statute determines that. The reality principle is about what is not covered by the statutory assumption.”
“The principle of reality is also relevant when interpreting a hypothesis required to be made.”