Even in that video the spotters weren't doing their jobs, you should always be prepared for the worst when spotting and that includes having you hands locked underneath the bar.
The safety bars are a great feature! There are a couple issues though. The first one being that not every lifter benches with a large enough arch, I know that even though I arch my back, I would barely clear the safety bar most times.
The second being that if a lifter isn't following the motion of bringing the bar slight back towards their face when they are pressing, it will drop on their ribs if they drop it. The bars won't protect against that.
Class I Total @ 198: 525/335/600 (1460)
"No citizen has the right to be an amateur in the matter of physical training.... What a disgrace it is for a man to grow old without ever seeing the beauty and strength of which his body is capable."