It does seem like a strange concept, but if you change strings in X2Goclient that linguist-qt4 is looking for, won't that trigger the "Translation needs to be updated" flag? If so, every change would send translators scrambling to check what needs to be updated, even though nothing actually needs to be updated... just a thought. Maybe you could try it out with one string to see what actually happens.
This actually was my concern, too. On the other hand I can understand Alex. This awkward situation of original strings changing, however, will only occur once, if we do a complete proof-reading of the originals in one go.
I can't say I'm all that positive about possibly having to retranslate all strings, last time I checked it was 469 strings. I can understand the will to correct the strings in the code, but if it breaks thousands of translated strings in the process I would definitley prefer an "english to english" translation instead. No end user would know the difference. If Qt Linguist is smart enough to pair up corrected strings in the code with the old translation (which only would require reconfirmation of the translation), I'm less apprehensive. Cheers, Daniel