Reciting the Tashahhud Twice
Question
Repeating the tashahhud in the final sitting (qa'da) does not make sajda al-sahw wajib — you wrote in your answer that this act is thana' (praise) and du'a. But a doubt arises: exiting the prayer by means of the salam is wajib, and here it has been delayed. For this reason the prostration ought to become wajib. Kindly remove this doubt.
Answer
In the final sitting, after the tashahhud, there are the salawat and a transmitted (ma'thur) du'a, and many du'as have been transmitted; it is not the case that one should content oneself with the barest minimum and that giving the salam and exiting the prayer become wajib immediately.
Source: Fatawa Mahmudiyya
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