1. The word "Mutlaqan" (at all) here, does not comply with our understanding that when we realise a mistake we do not leave it and go to the right opinion; how is it the case then if I follow a mujtahid and then discover later that he is a hypocrite wrongdoer (fasiq) do I remain as a follower to him? And if I discover that this mujtahid that I follow has a weak opinion, do I continue in following him? If for example I realise that I followed him in a prohibited issue that is based on a very weak hadeeth... do I continue following what I took from him?
2. In the book The System of Islam, it also mentions that the mujtahid is allowed to leave his opinion for the benefit of the Muslims. Same as what took place with Othman (ra) during his Bay'ah. I would like to see a narration of the story, when looking for it I did not see a correction for it, instead what I found is that it is unacceptable. Are there other correct narrations? Can you please provide evidence from the consensus of the companions to permit imitation in opinion?
3. Can one action achieve more than one value or not, for instance if you study a specific discipline and your aim is to please Allah and also a material gain.