Gerrit Lösch's public talk, Mexico 2009, listen from 25:15.
He says:
...the first edition of NWT in English had an... interesting translation of Matthew 24:45 ... it seems that the NWT... its first edition promoted that idea (that every individual Christian can be a faithful and discreet slave) by saying "Who really is A faithful and discreet slave...". If you look up the first edition of the NWT it said this way - "Who really is A...", it didn't say "THE faithful and discreet slave..." ... But in the next... in the revision of the NWT this was corrected... And you know why? In the Greek original language it says (for those who may know Greek): Τίς ἄρα ἐστὶν ὁ πιστὸς δοῦλος καὶ φρόνιμος... And "ὁ" means "THE"... The Greek unquestionably does not say here "A faithful slave", but "THE faithful slave"... and that's why it was put in subsequent version of the NWT this way...
By this verse you can check if you really have THE very first 1950 edition, or later revision.
And now, darkspilver - between You and I - WHO really is making it up? ;-)