>After all, that's what early English decisions themselves frequently did.
Not really. What's commonly called English Common Law is itself an Anglo-Saxon bastardization of Norman Law. Even American Law borrows directly from Norman Law in the formers now dwindling but still surviving usage of Latin.
>They were based on logic, by reference to statutory text, and by weighing the pros and cons of various alternatives, not precedent.
While I agree with the premise that is how law should be, that's generally not how it was nor is it so simple to accomplish. A quote to one should remember is that "[A]ny Anglo-American lawyer must cope with a sneaking feeling that there is no such thing as first principles, just one damned case after another."