Optim: reimplementing List.Compare extension via hash->sort approach - Only implemented for ref types for now, but can be extended to value-types as well - Has a limitation of requiring no duiplicates in queries lists - Dependent on the hash quality - we have a slow, quadratic path when a hash collision occurs - Measured performance - largest case (2048, 512) is an order faster than previous impl (0.75ms vs 12.5ms) Goal was to reduce the number of hash lookups from the original algorithm and to reduce it's quadratic nature. Tests: Ran the unit tests - all pass