Aldebaran said:
That it can happen and happens does not make it a condition.
I'm afraid it does. No matter how self-aware you might be, or think you might be, you cannot dial out your own views completely.
Only counts in environments where such documentation is possible and accessible at that. Contemporan history is not my field anyway.

But you are correct that when studying contemporan history you more easily get lured into a subjective approach, even on subconsious level.
It's a good generalisation. The volume of, for example, Parliamentary documents from the nineteenth century is many times greater than for the eighteenth. The same applies in pretty much every area in whcih documents have been generated and preserved. really, only when studying non-literary societies does the problem not arise.
However, it's a common observation amongst modern historians that premodernists, since they work with a far less comprehensive array of written sources, have to do more extrapolation to fill in the gaps! That is a process just as subjective, in fact more so, than selecting which of a vast array of written sources is most useful.
Yet if you are not enough aware of your own background and of how that could influence or cloud your views, you better stay out of the field of history studies.
That is what I have been arguing all along! You
must be aware of your own background, and of how that skews your perspective. Where we differ is that you think it is possible to rise above that, whereas I don't. You can compensate for it, if course, and reduce subjectivity to a minimum, but it remains there nonetheless.
Suggesting a new line does not equal inserting subjective reading and interpretation. It means you saw or chose other possibilities to approach a subject then what is done before or what is generally seen as "acceptable and accepted".
Of course. I never suggested otherwise. But again,
you see and choose those possibilities, though obviously within the limits of that the sources show. You don't really think that your own mentality has no influence on what possibilities you see and favour, do you?
It isn't exactly the most easy way, in none of its aspects, while in contrast a partial, subjective approach is the most easy thing to do.
I would suggest that the easiest thing to do is simply to regurgitate primary sourgces, which is also the least subjective approach. But it's also only half the job. If my life sonsisted solely of writing summaries of what was contained in various archives it would be very easy, and rather boring.
Placing sources in their historical context does not change the source itself, nor its contenance, nor what it meant to the writer or the people of that time. The goal should be to add to the understanding thereof in this time period. That the weight and impact of that meaning differs is inavoidable and only normal. We are not what or how those people where, let alone eye-witnesses of the subject under study.
Again, I don't take great issue with most of what you say, except that you seem to have missed my point about context. It is precisely the historian's contrextual knowledge that enables a source to 'add to the understanding ... [of the] period.' A document on its own often says little - it is a fallacy that 'the sources speak for themselves - but placing it in its context, and highlighting the intention of the author 'adds value' to it. But again, because understanding of context and interpretation of the author's intentions both involve some guesswork, the sort of objectivity you seem to be claiming you can pursue becomes impossible.
Resolving ambiguities and reparing faults or filling blanks (in primary documents, copies, parallel copies and/or their descendants for example) does not change the text. The goals is to get as close as possible to the original.
Of course, but with respect, resolving ambiguities
can 'change the text.' It goes back to what I said above about authorial intent, and the example I used in a previous post about politicians' speeches. Language isn't that precise a tool: different readers will read slightly different meanings into the same text, and writers will sometimes (as in the case of politicians) exploit the fact that, up to a point, we hear what we want to hear. Now, acknowledging all of this doesn't mean that I go along with the hyper-relativist (postmodernist) view that only the reader invests texts with meaning, and that therefore there is no such thing as any one correct interpretation. That's just nonsense: you can't read The Bible as a phone directory no matter how hard you try. However, it does mean that - as you come close to suggesting - the reader must always be aware that he will often invest certain parts of a text with a slightly, but sometimes significantly, different meaning. Two different people may well, then, resolve an ambiguity in a document in two different ways.
When you do primary and comparative parallel source research this involves historical linguistics, text history, text restauration and its critique.
Of course. But remember, written prose texts are not the only sources out there. Different techniques are needed when dealing with sources as diverse as published statistics, folk songs, trade directories and the minutes of evidence of government enquiries, to pull a few examples out of thin air. Some of those techniques claim to be new schools of historical thought in themselves...
Language is a very difficult and complex tool. If you aren't skilled enough in it you should stay away from trying to interprete historical sources written in it. If a source is unclear the historian using it should take notice and mention it.
I think I've acknowledged how complex a tool language is! But that is what makes it interesting, isn't it? You are of course right to suggest that an essential skill for a historian is the ability to interpret and understand language, but I would suggest that there are a great many other skills besides. And as a final observation, it is not only language that can be ambiguous and unclear: no source tells more seductive lies than a neat set of printed figures...