When people trade insults, there is often much dispute as to who has burned who. Now, finally, this can be evaluated scientifically:
Comeback Effectiveness (CE) = (c1-c0) / (t1-t0)
A comeback is considered effective if CE is greater than 1.
If the elapsed time before comeback is too long, CE will drop below 1. For example if you think of a great response on the car ride home, CE will tend toward zero regardless of how clever you are.
If the comeback is less effective than the original insult, CE will be negative.
If CE < 1, you have both the curse of the original insult and the shame of your lame comeback. Your insultor is now jusitified in saying something like "nice comeback!" You should probably go home and have a good cry.
If CE > 1, you have successfully burned the the original insultor. Good show sir! Example:
But beware - your attacker may now issue a comeback-counter which can be evaluated in similar fashion. Example: