Just a message to brother GreatChinese:
1. I know full well that if you see someone in a state if worry, despite knowing what is wrong you can ask them 'what is the matter?' However, you must consider my argument is built on the question and the response. Not only does he ask him whats wrong, Umar replies that should he convert to Islam, the people threaten they would kill or harm him. However, Al-'As not only asked him what is wrong after seeing him in a fearful state, Umar did not reply 'they are still out to harm me', or 'They continue to harm me'. Rather he says 'If he were to convert to Islam, they threaten to kill/harm him'. The reality is, Al-'As already knew this. Umar knew that Al-'As knew this. The way the conversation went is not how you would expect it to go if Umar ibn al-Khattab had fought the Kuffar dawn to dusk, attacked them and then they resolved to try to harm him. If we accept brother Noors argument, then Umar ought to have said 'they are still out to try to harm me'. However, the way Umar phrases it implies he may have converted, they may have known, and that they were now planning to try to punish him for it, which is why he had hidden in fear in his house.
I am not claiming accept this point on a stand alone, but when taken with the other points, together, it is a compelling argument as to why i personally believe the two versions are not reconcilable.
2. A massive part of brother Noors argument is the first action by Al-'As did not signify protection, but that when they recognised he had actually protected him, they then respected and feared Al-'As and put weight into his protection. Your points about al-Abbas therefore do not apply. Al-'As commanded such respect that when they knew he was under their protection, they dispersed. In the example of al-Abbas they kept attacking and al-Abbas had to kneel over and rescue him twice. This is an extremely important point.
So when you take into account the fact not only did al-'As not know what seemed to be the worry with Umar, but the fact Umar had to explicitly state was he to convert to Islam they threatened to kill him (he had already converted and it was known). While it is not out of the question al-'As may have known this and Umar was already saying again what he had know, the wording supports my view, than your view. Had AL-'As known he would have been told "The people are still out to get me for having converted to Islam". This would fit perfectly with a narrative that they had attacked him before. However , the fact he said they would attack him was he to convert to Islam strongly supports the interpretation that they had heard rumours he had converted and had not explicitly attacked him yet, which is why Umar having known that they would harm him was in his house.
2B. Protection was granted in the tradition of Musnad Ahmad. Had the people not have valued his protection, it would have not worked by him merely telling them to go away and not to harm him in the tradition of Bukhari. Me and Noor agree that protection given by Al-'As had strong weight, such that that they would disperse and not return and so our debate is whether or not what is in Musnad can be considered protection? Therefore in addition to what i have mentioned your point about al-Abbas is not evidence.
I strongly feel anyone reading this objectively will see where i am coming from.
3. In my posts i have consistently believed the protection given him was explicit, and in my later posts i clarified that i believe you do not need to claim 'someone is now under the protection of my tribe' for it to be support. Al-'As never did that in Bukhari. All he said was no-one can harm Umar.
4. It makes absolutely no sense for Umar ibn al-Khattab to start fighting dawn to dusk , beating up the Kuffar, poking their eyes, sitting on their chests, going from door to door and proclaiming his Islam knowing full well this will aggravate them and make them want to harm him , and the in another version hiding in his home out of fear that if they had known he converted they would kill or harm him.
The versions can not be rationally reconciled. Rather the most accurate understanding is that when Umar converted to Islam, the polytheists heard about it, and Umar had subsequently heard that they may harm him, and so he hid in his home our of fear, because he was worried how they would react. Al-'As who was an Ally and from the tribe of those who were allies came to see Umar and asked him why he was concerned and worried, and learned that he fears he would be hurt. Upon this, Al-'As went out and made his way to those wanting to harm him, and asked them where they were going in the accusative sense knowing well well where they were going. They did not know Al-As knew! When they told him and Al-'As told them no-one should harm Umar, then they retreated.
If the tradition in Musnad was authentic, why on earth would they have needed to tell Al-As knowing full well he protected Umar and would not permit them to harm him? He was already under his protection and so they did not need to tell al-'As that , because they saw him defiantly come into his defence earlier. Rather this was the first time Al'As or the polytheists were addressing each other about Umar, and as soon as they recognised Umar had an Ally, they dispersed. They did not realise Al-'As would defend Umar, and when they found out he indeed would defend him, they recognised Umar had a defender in a power man like Al-'As and that they would not harm him.
Brothers have to accept this is no insult to Khalifah Umar. I would be lying if i claimed i would not fear if i knew people were out to harm me for converting. Most of us on this forum would have some fear in our hearts. In fact, it might even be a merit of Umar that he converted knowing people may be out to harm him. However, i sincerely do not feel the stories and tales of him fighting dawn to dusk, gloating to the polytheists, poking their eyes, and sitting on their chests is tenable, makes sense, or can be reconciled with the more authentic version of events in al-Bukhari.