How sound are the claims regarding Imam Ali's refusal to pledge allegiance to Abu Bakr (may Allah be pleased with him), and regarding Uthman's beating of Ammar (may Allah be pleased with them both) in Ali's presence without his intervention?

The Companions are human beings; they are afflicted by what afflicts humans in terms of disagreement. However, they are the quickest to goodness, the most knowledgeable of the truth, and the most repentant of error. It is obligatory to refrain from discussing the disagreements that occurred among them. It has been authentically reported from Ali that he said: "The best of this Ummah after its Prophet are Abu Bakr and Umar." Ali's pledge of allegiance to Abu Bakr is affirmed in the Two Sahihs, even if it was delayed for several months due to Ali's resentment towards Abu Bakr and Umar for not consulting him in the matter of the caliphate, and Ali's agreement with Fatimah in her estrangement from Abu Bakr due to her anger over Abu Bakr's rejection of her claim regarding the inheritance. It has not been proven that Uthman struck Ammar, and all that has been narrated regarding this has a weak chain of transmission. Rather, what is confirmed is that Uthman did not order Ammar to be struck.