This. There are no flip-covers on the switches in any of the photos I've seen. Additionally, it looks like the side guards are only on the left and right sides of the pair of cutoff switches, not in-between the two switches. So if one bumped one switch, seems like it would be very easy to bump them both.
There's a metal nib on the switch and switch housing preventing it from being bumped. There's also a spring holding it down so it can't bounce up. The distance and required force makes switching them at the same time impossible, thus the 1 second difference. This was absolutely an intentional act.
One can easily switch them with two fingers at the same time.
I tried (with similar switches.): Works. If the locking mechanism fails, even unintentionally.
Getting loose, wristworn jewlery snatched and then pull: Works.
My question to Boeing is:
Why did you cover the neighbouring (stabilizer cut-off, IIRC) switches with red springloaded flip-covers, but not the fuel cut-off switches?