It seems that the Gemmora leads to say the Halacha is like Rav Yochanan that whwn going up a ladder and the rung falls and kills someone that this is chaiv Galut since Yerida L"Zorech Aliyah. But, when the Gemmora attempts to ask Leima K"Tanai, the Gemmorah is supporting the view that argues on Rav Yochanan that only in a weak ladder is it Yeridah but a normal ladder would be ALiyah. Is the Gemmorah retracting on its view? Thank You
Ron Finberg, Ramat Bet Shemesh Israel
Tosfos (DH "v'Ee Ba'is Aima") is bothered by a similar (stronger) question, and answers that when the Gemara says that "that everyone holds this is Aliyah," it doesn't mean that "Yeridah she'Hi Tzorech Aliyah" is Aliyah. It merely means that in a case where the rung is taught and not wormy there is no real Yeridah to speak of, and therefore it is not Yeridah. It is not coming to argue on Rebbi Yochanan (or the Beraisa above which explicitly included Yeridah she'Hi Tzorech Aliyah).
All the best,
Yaakov Montrose