This reminds of a really interesting study by a sociologist called Edwin Lemert - he looked at stuttering among NW coast Indian tribes and found that stuttering only existed among those tribes which put an emphasis on public speaking (i.e. status was linked to your ability to speak in public), in those tribes where there was no such public-speaking-status norm, stuttering simply didn't exist!
Lucky we've got the Net!
I wonder why they got those Results?
the idea is that stuttering is socially constructed - i.e. it's only emerges because of the stress induced by public speaking. It's an extreme development of labelling theory - someone fails at school because they are labelled a failure... someone develops a stutter because society says they MUST speak in public and be good at it.