The binding legal principles established are: (1) Annexing multiple sets of particulars of claim to a summons, rather than one composite set, does not constitute a fatal irregularity under the Uniform Rules where no prejudice is shown; (2) Under Rule 10(1), multiple plaintiffs may join in a single action where their claims depend upon substantially the same questions of law or fact - 'substantially' means there must be significant factual overlap but not identical facts; (3) Where multiple delictual claims arise from incidents at the same time and place, involve common witnesses, and share significantly overlapping factual issues, they satisfy the test for joinder even if specific details of individual assaults, injuries and damages differ; (4) Considerations of convenience, efficiency, avoidance of inconsistent findings, and economy of judicial resources are relevant to determining whether joinder is appropriate; (5) Technical objections to procedural steps should not be permitted to interfere with the expeditious and inexpensive decision of cases on their merits in the absence of prejudice to the opposing party.