you raise a very important point here and i know what you mean. of course the topic the a aobt-user has translated should be kept up to date and if necessary he should identify himself with it in a way. but it is also the case that maybe a few of us lose the complete overview of their work due to the number of own translations and therefore the maintenance of the local threads is neglected - here the own organization is needed.
i personally try to keep my translations up to date. here is a topic that can be used to see if the actual translator keeps an eye on the updates and keeps his translation up to date:

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and that's all i want to say about it. find out for yourself...