AB Dual Hyd failure describes as "Dimensioning failure"

[BuzzBox]

The introduction to Dual Hydraulic Failures in our 'anglicised' A330/A340 FCTM reads as follows:

Dual hydraulic failures however, although unlikely, are significant due to the following consequences:

• Loss of AP
• Flight control law degradation (F/CTL PROT)
• Landing in abnormal configuration
• Extensive ECAM procedures with associated workload and task-sharing considerations
• Significant considerations for approach, landing and go-around.

So yes, 'dimensioning' seems to imply 'significant'.