I guessed everything would be ok in the vid, but even so I cringed and almost didn't watch it.
Did you notice how he held his finger very slowly to the blade, ie he didn't run his hand in as in a normal accident scenario....not that confident then eh....

I bet the tool in real use is a PIA, spot of damp in your timber and....

lets face it, timber is often damp....load of rubbish if you ask me. One trip of the safety device and I bet any owner just switches it off and uses it as a normal saw...