Just to be clear, if the tug is not the jump ship, then it can be smaller than the tow. In other words, a 10kton tug could tow your 100kton platform through a jump gate, or through a jump point that had a 100kton jump ship stationed there, or in a TG that had a 100kton jump ship.
And also to be clear: the tug and tow masses are treated independently for jumping. So you only need a 100kton jump ship in the example above, not 110kton.
John