Mad Max comes to mind. Take 'em out one by one
But seriously, a human wave is going to swallow anyone who can't impede its progress. A weapon naturally helps slow those in front, and in turn those following, either visually, or running into the backs of those first re-assessing the situation.
Short of a defender's weapon in your face, a sprawled comrade who won't kindly sit still so you may more aptly resume your bloodthirsty mindless assault can also serve as an impediment.
Obviously the odds do not favor a solitary defender, but I don't think we should so easily shrug our shoulders and say, "Well, I'll just stay out of Malaysia". Logic, oddly enough, still holds in these situations, even if the logical conclusion still results in a dirt nap.
If-Then-Else or 'cause&effect' is not simply tossed out the window.
Without knowing possibilities exist, you won't use them. Randori practice exposes you to those possibilities, so I would propose that yes, randori would help in this bizarre situation.
No, you will not be claiming the severed limbs of your enemies as your own property, a la The Bride(clickety)
, but I wager that in 20 tests, you would see a statistically significant difference between trained and untrained defenders.
I believe there are youtube vids of Seagal's dojo randori (age's past, some sort of documentary). It seemed to consist of 3 or 4 people dead-rushing nage, and simply trying to subdue them. It seemed mostly that nage was dragged down in the first 5 to 10 seconds.
The practice, if I recall correctly, was to expose nage to the fear/intensity of the onslaught, partly inspired by the fact that you can't do anything to protect yourself for a couple reasons, 1 being you shouldn't trully attempt to incapacitate your uke, 2 you won't want to, as you're likely friends with your ukes. Though it's been a long while since I've seen it, may still have the vids on my old hard-drive, If I can't find them on Youtube, I may just put them up!