@syg If you happen around to answer more questions: Why going with only Sealed prototypes for structs? Personally, I would assume that with static initializer b

@syg If you happen around to answer more questions: Why going with only Sealed prototypes for structs? Personally, I would assume that with static initializer blocks we could well go with "initially Sealed" with "Frozen once class initialization completes". ie. Make the last step of "StructDefinitionEvaluation" AO "SetIntegrityLevel(F, FROZEN)". This way I'd assume eg. decorators would be usable on struct fields and methods, but engines would be safe to cache prototype method lookup result values without any validity cell mechanics. I would assume this could make prototype method calls on structs very fast indeed.