Well, actually each of us is the result of some slacker that got there after the initial faster ones wore down the coating of the ova. The fastest ones got tired doing all the work to let us slower fresh arrivals scoot in.
Hm. That's a new one. All of the data I'd seen (which is admittedly years old now) indicated that sperm operated in a pitbull-like fashion and didn't give up once they'd latched on.
'Course, there's also been discoveries of "killer sperm" that make their (albeit short) living out of attacking and slowing down other sperm en route to the egg. Not quite sure what to make of that...
-Jay