Multiple wires, one terminal - when acceptable?

So we all know that it's perfectly acceptable to break out a large gauge wire into multiple smaller gauge wires to make a layup work. What I don't see much about though is what happens at the other end? Say for example a radiator fan... if we send 2x 16 awg wires for power down the harness, do we just terminate them both into the one terminal at the motor end, compromising the cable seal? Or do we splice it back to a single 14 awg at the final transition so the is no issue with cable sealing? This seems preferred however more splices means more bulk and more points of failure... Thus the dilemma I am facing

I would appreciate your thoughts.

I personally would keep fewer points of failure and compromise the seal unless it was on a watercraft or high water logged area, also take into consideration how much the loom would move at that area during use,

A correctly sized closed barrel splice, strain relieved in SCL, then kapton or PTFE tape and a heat moulded boot is an extremely low percentage failure point, especially compared to an OE contact that has been crimped in a less than ideal fashion. The wire seal is used for strain relief as well as sealing so it will likely compromising more than just the sealing. You could always pot the fan with a flying lead and the appropriate number of 16 AWG conductors and terminate those in an appropriately size Autosport connector if you were worried about a splice.