“The court is concerned to ensure that the proposed expenditure is at least necessary for the proper purposes of the defence. The claimant is not entitled to monitor each of the steps the defendant proposes to take in litigation but it would be wrong, for example, for certain expenditures to be made prematurely or where there is a real danger that it will be thrown away. This is because part of the exercise of a discretion involves taking into account the risks of injustice to a claimant in having his own money used to litigate against him so the court will act more cautiously to minimise the wastage of funds.”