DOVBEAR: Chazal were not in any position to know how people thought or acted thousands of years earlier. In particular, they had no way of knowing if earlier generations were actually aware of the Rabbinic interpretation of Ben Sorer U'Morer. Though its true that the verses, as they were read at the very end of the second commonwealth, demand various pre-requisites that make a rebellious son almost impossible to convict and punish, we don't know that this reading was accepted at earlier times. Perhaps the Sages of the Persian period, or the Sages of the first commonwealth interpreted the verses differently.
@YEEDLE: Correct. But most probably they knew. And according to what they tell us, they knew/believed that they had the same interpretation that was passed down to them from Sinai. According to what they knew/believed, it makes absolutely sense to say that the rebellious child phenomenon never came about. You, on the other hand, believe that their interpretation was a product of their generation. So you can't say that it did/didn't happen. They, from their vantage point, can.
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