Is understanding everything in Arabic in as short a time as possible realistic? Can one or two books gain you mastery in Arabic?
Learning and mastering everything depends on the size of the language. If the language is small and basic then you could learn just about everything that the language has to offer. As for other languages, like Arabic, you may be able to understand and master everything but on the other hand, you might not need to master everything in one go or one course. Arabic is not a small language, it is vast, so learning will take a while. Focussing on a particular area, within the language, may help to bring you closer to mastery, in a particular field or specific concepts at least.
Learning and understanding everything takes dedication and sacrifice. Understanding everything in Arabic may be a nice aim to have but whether or not someone actually achieves it is another story.
Arabic has to be repeated for you to really benefit from it. So different books, tutors, exercises, courses, resources, countries visited and conversations will all help to contribute in there own little way. The more cycles and repetitions the more you understand and cement that understanding. In this way, you can keep learning new concepts and vocabulary but always be able to return to revise what you previously learnt.
Language learning has its approaches and methods but individuals also have varying aims, paces and sometimes deadlines which can all impact how quickly or slowly someone will learn. When learning Arabic one thing to remember is that you do not need to understand fully any one particular concept in one go, if it starts to get a little overwhelming take a break and then return to it in your own time or from a different angle etc. Don’t get bogged down by something you are not getting, move on and come back to that obstacle another time. Going over a little at a time regularly will serve as a good strategy.