1The General Steel/Dey principles governing summary dismissal of proceedings are not engaged on an application for leave to amend a pleading under UCPR r 375; the appropriate framework is the multi-factorial discretion derived from Aon Risk Services Australia Limited v Australian National University (2009) 239 CLR 175.
2A proposed amendment that foreshadows yet further amendments contingent on disclosure and expert evidence — effectively treating litigation as an investigative process — weighs heavily against the grant of leave, particularly where the plaintiff has had prior opportunities to plead its case and offers no satisfactory explanation for delay.
3Where multiple trial dates have been vacated and the proceeding has consumed significant judicial and party resources without progressing to trial, the court will give substantial weight to the prejudice to the court, the parties and other litigants from amendments that widen the scope of the litigation and risk further delay ('mission creep').
