No, by no means was it the only yardstick, they are so many events, so many traditons that point out the AHlul Bayt (as) and the succession of Imam ALi (As) that one would have to be blind from innermost not to see or understand.
nobody can deny the stature of hazrat ali as a sahabi as he was part of ashra mubashara. but there are few others who were most experienced, clsoe to prophet and judicious than hazrat ali (RA) keeping in view the fact that hazrat ali was relatively very young at the time of death of hazrat muhmmad. and prophet did not nominate neone for succession.
(only shia has this point of view of succession........)
hazrat abdul rehman bi auf (ra) reply to hazrat ali is worth considering in which he said:
( my dear nephew! a day will come when u will become caliph but currently u r novice in worldly affairs (government administration ) and there are many ppl available that are more experienced than u.
(from hussein heckal book an egyptian historian )
his prediction became true and eventually we see hazrat ali became caliph . beside we see that his tenure was not an ideal period in the islamic history filled with so many controversaries and war between different group of muslims. administration was not that gud (by no mean i want to say that hazrat ali was responsible for all this however he cuold not set the things right as hazrat abu bakar did when majority of the arab bacame prosteliyzed after the death of prophet but abu bakar succeed in setting the thing rights). chaos remain there untill the hazrat hasan did baith of hazrat muavia and things settled down and muslim got united again.
Let me ask you why Hazrat Muhammad was chosen for Prophethood and not his father etc? why was He (saw) chosen and not the first caliph Abu Bakr? You could go on forever. Hope you get the point how futile your question is.
i think u have given a very wrong example here. we are talking about the ahle bait and not prophethood . always like to like case is compared.
i think the real problem is that few shia scholars have tendecy of " cherry picking". whenever they see sth in praise of hazrat ali and his family in bukhari and shah sitta they take it and incase of ahadith in favours of othere sahaba they start saying that bukhari is not authentic.
as a muslim i think we shud give respect to all sahabas as the quran and hadith demands.