Postscript 24 November 2017 Dal Al Arkan was confirmed in Deutsche Bank AG v Sebastian Holdings Inc & Alexander Vik  EWHC 459 and in Dennis v TAG Group  EWHC 919 (Ch). Permission for service out of jurisdiction is not required since the (now) Article 24(5) rule applies regardless of domicile of the parties.
In Dar Al Arkan, the Court of Appeal has suggested that the Court’s reading of Article 22(5) of the Brussels I-Regulation in Choudhary was per incuriam (meaning, in short, without reference to relevant statutory law and case-law and hence not subject to the rule of precedent).
Article 22(5 provides for ‘exclusive jurisdiction’ ‘regardless of domicile’, ‘in proceedings concerned with the enforcement of judgments’, established for the ‘courts of the Member State in which the judgment has been or is to be enforced’. The key word for this exclusive jurisdictional ground is ‘enforcement’. ‘Proceedings concerned with the enforcement of judgments’ means ‘those proceedings which can arise from recourse to force, constraint or distraint on movable or immovable property in order to ensure the effective implementation of judgments and authentic instruments‘ (Raport Jenard).
Difficulties arising out of such proceedings come within the exclusive jurisdiction of the courts for the place of enforcement, as was already the case in a number of bilateral Treaties concluded between a number of the original States, and also in the internal private international law of those States.
The Jenard report does not quote a specific reason for the reasoning behind this exclusivity, however one assumes that such proceedings are so intimately linked to the use of judicial authority and indeed force, that any complications in their enforcement ought to be looked at exclusively by the courts of the very State whose judicial authorities are asked to carry out the enforcement. In the words of the Court of Justice: ‘the essential purpose of the exclusive jurisdiction of the courts of the place in which the judgment has been or is to be enforced is that it is only for the courts of the Member State on whose territory enforcement is sought to apply the rules concerning the action on that territory of the authorities responsible for enforcement.’ [Case C-261/90 Reichert v Dresdner Bank,  ECR 2149, para 26.).
Neither Convention, Regulation or Report Jenard clarify specifically for Article 22(5) whether the Article applies against non-EU domiciled defendants. In Choudhary, the Court of Appeal had held that it does not. However it had refrained from citing any relevant statutory or (ECJ) case-law authority. In Dar Al Arkan, the Court suggests that this renders judgment in Choudhary per incuriam in line of ECJ and scholarly authority. This is the right approach: the raison d’etre for Article 22(5) is a specific and narrowly construed one, as it is for all other parts of Article 22, in particular per the extract from Reichert, above. (A convincing case for Gleichlauf between court and applicable law).
For instance, the Article 22(5) ground for jurisdiction must not thwart jurisdiction of other courts who would have jurisdiction had the case not been brought as part of an enforcement difficulty. Therore, by way of example, the court which has jurisdiction on the basis of Article 22(5), cannot hear the defence against enforcement which is based on a request for compensation with a different mutual debt (Case 220/84, AS-Autoteile Service). Neither does Article 22(5) trump the enforcement Title of the Regulation.
Within those narrow confines, there is no reason not to extend the jurisdictional rule to defendants domiciled outside of the EU. Their non-dom status is immaterial to the proceedings. (Note that the issue on the ‘reflexive’ nature of 22(5) is not resolved by this judgment. Neither by the Brussels I recast, which does clarify (recital 14) that indeed non-EU domicile of the defendants is not relevant for the application of Article 24 of the new Brussels I-Regulation).