I'm still confused by what you are saying.
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But when we have
var observable = new can.Observe(foo);
now observable is said to be an instance of the class Constructor? But we can't say: observable is an instance of Constructor, or, observable is a constructor.
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No, observable is an instance of can.Observe (it's proto points to can.Observe.prototype), but also an instance of can.Construct (can.Observe.prototype.__proto__ == can.Construct.prototype).
I think Chrome's tools are misleading you. But I'm not sure .displayName is available in all browsers to correct this.
