Depends where someone cut it (really, how big of a problem is this, and does it really happen a lot on passages???). For most small N2K networks, the terminating resistor isn't necessarily that important. I have ran our network with a terminator removed several times for many hours with no problem.
So if one did decide on passage
to start wildly sawzalling around their boat and managed to cut the network backbone cable, one may only lose those items on the far side of the cut and keep those on the near side.
My advice to mitigate this problem is to run the network backbone through a metal or schedule 80 PVC conduit and post warning signs around the boat along the cable run telling you there is a buried cable there.
Or hide your sawzall when on passage