"The plaintiffs, however, have not put forward a single shred of fact or a single suggestion casting doubt on the fairness or accuracy of the executors' evidence on the subject of value. Indeed their complaint is this: 'We cannot do that without some materials and the reason why we want discovery is to enable us to test what the executors have said and to see whether or not we can find something on which to attack their estimate.' In ordinary litigation, of course, the ordinary rules of discovery enable litigants to conduct such an examination, but this is a very special jurisdiction under a very special Act governed by very special rules. The judge has ample power, if he is not satisfied or if he thinks there is a reasonable ground for doubting the accuracy of such an estimate as this, to require further evidence on the point, to summon the executors before him, to put questions to them and to subject them to cross-examination. If he thought that was the proper course and if the matter was a matter of doubt or if suspicion was aroused, that no doubt would be the course that he would take. But here we have what on the face of it is sworn testimony by reputable people, the accuracy of which has been subjected to the not too easy test of an investigation by a government department. Everybody who has a little experience of these matters knows that the valuation of shares in private companies is often an extremely difficult matter, and also, I think, everybody knows that where such shares come up for valuation for death duty purposes they are a subject-matter on which the death duty officials are particularly vigilant and particularly inquisitive. A judge who is asked to exercise his discretion in a case of that kind has to weigh in his mind these considerations. Here are plaintiffs who cannot suggest any doubt about this prima facie reliable method of arriving at the valuation, who merely ask for the instrument of discovery to be put into their hands to enable them to see if they can find something on which to attack it. If ever there was a case where a judge should decline to exercise a discretionary jurisdiction to grant an order for discovery, I think this is such a case. If any reasonable suggestion of doubt could be raised, I have no doubt the judge in his discretion under the power given to him by these specific rules would require further information."