s_allard wrote:A tutor, or some sort of external assistance, is a necessity because you cannot see and fix all your own mistakes alone. It's as simple as that. If you are satisfied with mediocrity at the advanced or mastery level, then a tutor is certainly not a necessity.
I'm sorry, but if you don't know how to correct your mistakes in written language with the help of google and a grammar checker, then you need to probably go back and fix your basic grammar, which is a B2 activity! If you are an advanced student, i.e. C1+, you will have already identified the main areas where you are likely to make mistakes - prepositions, idioms, maybe certain tenses or in some languages cases. And of course you will also simply know when you're making a mistake because it sounds wrong! Google is usually enough to correct mistakes in written language at that level. Basically the need for grammar books and massive input to get your mistake detection machine going will put you squarely in B2+ rather than the advanced category C1-C2 and in this case a tutor can indeed still help.
I'm now starting to wonder whether this whole discussion isn't based on a simple misunderstanding: How advanced does a student have to be to fall into the advanced category that the original statement mentions? I personally believe that you haven't really reached C1 if you can't send an email or any other kind of correspondence specific to your necessities without worrying about mistakes. In fact, my own standard for C1 would be to be able to submit an essay at a TL university without having a native speaker proofread it. After all C1 writing requirements are this:
"Can produce clear, well-structured, detailed text on complex subjects, showing controlled use of organizational patterns, connectors and cohesive devices."
University lecturers who often have to grade essays of foreigners tend to agree that grammar mistakes will ruin the clarity of a text. Texts on complex subjects require precision and grammar mistakes will make precision impossible. Same goes for simple writing conventions: Germans who write in English have a tendency to use too long sentence. Proofreading essays in English for Germans usually entails cutting every sentence in half. No English native will judge a text to be clear if it contains sentences that are half a page long! So, if you are unfamiliar with the writing conventions of a language and still produce grammar mistakes in written language you simply haven't reached C1/advanced level yet. There simply is no space for mediocrity at an advanced level.
So, the real question is here: Can a tutor help with going from C1 requirements to C2 requirements?
"Can summarize information from different spoken and written sources, reconstructing arguments and accounts in a coherent presentation.
Can express themselves spontaneously, very fluently and precisely, differentiating finer shades of meaning even in the most complex situations."
Sure, someone can definitely help with that, but only if they are able to understand the different kind of written and spoken sources and the topics that are the basis for your spontaneous expression! If my C2 requirement is to precisely express different shades of meaning in relation to the finer points of the philosophy of Derrida, a language teacher has no chance to even follow what's going on. If my requirement is to quickly discuss a complex computer programming problem that requires high level abstract thinking and problem solving abilities to even understand the problem in the first place, any language teacher would be completely lost!
To be perfectly honest, most native speakers fail at these requirements actually, even when they are experts in their field. Most programmers I know can't express themselves coherently at all without the use of a huge arsenal of diagrams and drawings. A surprisingly large number of philosophers don't even understand Derrida and even those who do are usually barely understandable themselves. In their native language!!! One philosopher told me that he considers reading Derrida a waste of lifetime. This stuff is really at the extreme limit of abstract thinking. In fact, I only know very few people who can express themselves coherently about Derrida OR highly complex programming problems, although I've met a large number of programmers and philosophers. The number of people who can do BOTH is extremely small - I think I might actually know every single one of them personally, it's barely a handful on the entire planet! How could I expect a language teacher to be of any use to me when the challenge is this?! Ideally you would need an expert in your own field to be your tutor and then there might be a chance that they can help you.
The best environment to move from C1 to C2 is of course a TL university, and the difference between an acceptable essay and a good essay is actually C1 vs C2. Now, the only reason why B2 is the usual language requirement for bachelor degrees is that 1. you can pay people to proofread your essays and 2. in most fields the topics at bachelor level are not extremely complex yet. Masters programs in certain humanities fields require at least C1, because you simply can't have a complex discussion in these fields with someone who can't use language precisely. A C1 level student will have problems participating in seminars, but they will be able to pass the assignments. If they want to not just pass, but to participate and excel, then C2 is definitely needed at this level.
So, I insist, language teachers are not qualified to help with C1-C2 level problems, unless you restrict yourself to working on the narrow set of sources required for the C2 level proficiency exam. Going to a TL university is usually way too expensive and a logistical problem. So, the best tutor to hire at this level would probably be a native language masters student in your own field.