When an upstream PO file contains fuzzy strings, these are marked as being made by the Last-Translator. This is not correct. It was the fuzzy logic of msgmerge that made these 'translations', and they are almost always wrong. Attributing them to the last translator makes this translator look rather stupid.
So fuzzy strings should either be attributed to a fictive translator, say 'Fuzzy Logic' or 'Msgmerge', or they should be discarded entirely -- see also bug #1066. The advantage of this latter option is that there is no need to fix bug #78917 (differentiating the 'fuzzy' and 'needs review' flags).
An example: cpio-2.8 came with a few new msgids. Among them was "Not enough arguments", which msgmerge had fuzzily 'translated' with the opposite meaning in Dutch, "Te veel argumenten", because that was the most similar msgid: "Too many arguments".
Assigning all translations in a PO file to last-translator is as wrong as it is assigning them for fuzzy translations (iow, not all translations assigned to last-translator have been done by them). However, we need this to be able to reconstruct the PO file as it was when we imported it.
So, I'd still prefer to correctly differentiate between fuzzy and needs review flags, which is the correct solution.
And I think we have constraints in the database which require that any suggestion has someone who submitted it, so we can't just set it as done by nobody. This is basically a problem of missing data and fuzzy/needsreview confusion.