I think there's something in it, but I agree that
just about any shock will
make muscles do uncontrolled things.
The most "shocking" thing about getting shocked with house current is
not the pain, nor the involuntary muscle movement, but the surprise.
Most people never expect to get shocked, and the weird sensation will
cause a panic, with the brain thinking "pull out!" and the muscles
perhaps not following orders exactly, all with perhaps a little bit of
a flash-bang effect - and then the injury happens (falling off
ladders, etc.). Look at electricians, especially ones that repair old
installations. They get bitten all the time, and they really don't
flinch much at all. They are used to getting shocked. 120 V AC really
does not hurt much at all, and 240 V is only slightly more painful -
and I am not talking about whack your thumb with the hammer pain,
here. A fair number of electricians actually test wires with their
fingers. It is mostly just a very weird sensation. Get used to it,
respect it, and it is not really an issue.
--
Will