For these narrations are not contradictory to what we have mentioned, because they contain the element of choice regarding the taslim (salutation). And for the one who connects the rak‘ahs (without separating them), then it is not permissible for him to perform the taslim in that form. And when there is choice involved, we interpret it to refer to the specific form of taslim, according to us, whoever says ‘Peace be upon us and upon the righteous servants of Allah سبحانه وتعالى ‘ in the tashahhud, his prayer is cut off; and if after that he says ‘Peace be upon you and the mercy of Allah سبحانه وتعالى ‘, it is permissible, and if he does not say it, that is also permissible. Thus, the choice pertains to this type of taslim. And if there were a clear prohibition of taslim in those reports, it would not be obligatory to act upon them, because the narrations establishing the obligation of taslim are more numerous, and it is not permissible to abandon the greater number for the lesser unless there is a clear proof requiring it. It is also possible that these reports were issued by way of taqiyya (precautionary dissimulation), because they conform with the views of the general public (non-Shia jurists), and whatever is issued in such a manner is not obligatory to act upon. It is also possible that by "taslim" was meant the permission to speak and other such acts that become allowed through taslim, and that it was referred to as “taslim” because it serves as the cause for that permission. This type of statement is something in which the person is given a choice, if he wishes, he may speak, and if he wishes, he may begin the witr without speaking. And what further clarifies what we have just mentioned is what was narrated:
Commentary #53