I'd agree with pziemlewicz that from an operations point of view I'd like find a problem in my process not with the final inspection of my parts.
Some things to consider from my point of view:
- you could validate a sub-process against a sub-assembly tensile spec, but monitor it using the relevant process parameters determined in the OQ of the validation of the sub-process instead of actual tensile tests on the sub-assembly
- if for a development project you need to perform design verification and validation with final, finished devices this should cover all aspects of a PPQ
- if you validate each sub-process separately, any change to this sub-process later on only needs validation on that level, not on the level on the final, finished device, i.e. a DV&V or PPQ