The last phrase was contradicted by a member of the Bush Administration at the Cato conference referenced above.
Her response indicated there would be NO end to renewals.
I don't think multiple or even unlimited renewals contradicts the phrase "have an end". That phrase only contrasts the guest worker visas with legal permanent residence or citizenship. Those statuses literally do not have an end date. Regardless of how many times you renew the visa, it still has an end date specified.
JMO, of course. We're all trying to read tea leaves here.
She's not the one in charge.