1. Ability to partially parse during areas of uncertainty.
   
2. When do discriminators apply on arrays with minOccurs > 0?
   
   Array occurrences less that minOccurs are mandatory so are not points of uncertainty. The point of uncertainty starts after minOccurs have been found so that is when the discriminator should be applied. What should the discriminator resolve before minOccurs are found. Maybe the use case for identifiers on discriminators.

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