Loren Wiseman framed the concept nicely back in 1980. Page 3.
I would like to take some space here to deal with a question we are often asked... How much can I, as referee, modify the rules, and how closely must I stick to the published Traveller Imperium?
First of all... [the OTU] is to help the referee ... Referees who do not wish to use our materials or who wish to use only parts of it are free to do so, adapting anything to fit as is necessary. ... Referees are free to make any changes to the rules they may with, but with a few caveats:
First: Bear in mind that the rules are interlinked to a great degree. ...
Second: Be careful not to destroy balance of play. ...
Third: Do not modify the basic tenet of Traveller -- that the speed of communication is limited to the speed of travel. ...