At page 572 of Spry, Equitable Remedies, 5th Ed, the learned author emphasises the balance of convenience and what the justice of the case requires: ".... On all interlocutory applications the hardship or prejudice that may ensue if relief is granted or if conversely it is refused is weighed with other relevant considerations, including the strength of the plaintiff's case (see generally American Cynamid Co v. Ethicon Ltd [1975] AC 396....); and although the court acts with caution, a mandatory order is made if the balance of justice so requires. But when the plaintiff is seeking on an interlocutory application an order for the specific performance of part or all of the defendant's obligations under a contract, being relief that is ordinarily granted only at the final hearing, that relief is, at least in the absence of special circumstances, granted only if its refusal would give rise to disproportionate prejudice or hardship to the plaintiff, as against the prejudice or hardship 8 that its grant will cause the defendant (Films Rover International Ltd v. Cannon Film Sales Ltd [1987] 1 WLR 670). Since account is taken of the strength of the plaintiff's case, the more probable it appears that he will succeed at the final hearing or in other relevant proceedings, the less reluctance to intervene will be shown by the court (Locabail InternationalFinance Ltd v. Agroexport [1986] 1 WLR 657)."