I wouldn't, because many times a person who allows himself to be bullied does so out of believing s/he wants to "be the better person" and not "fight dirty" (if only verbally).
Then, too, I think of my two sons (at different times) when they were little boys and being bullied. Both were normal, active, strong, little boys who happened to have a sense of right and wrong. Both said (at different times and about their bully), "I could really hurt him if I wanted to, but I don't want to." They didn't want to seriously injure another kid because they were decent kids (and I think they were also sensible enough to realize that even if they did want to seriously harm their bully there would be serious consequences).
There are a lot of reasons someone will put up with rotten treatment from someone else that have nothing to do with weakness. In fact, sometimes it's a person's character, strength, ability to control his own anger, or sense of decency that make him refuse to "stoop to someone else's level".