i myself have been hit with severe turbulence due to a pocket preceding a storm, in the middle of the cabin the aircraft actually appeared to bend, this may or may not have been the case but i know how it looked, you could almost see the floor ripple. the jolt passed down the aircraft and 3 crew were thrown and struck the ceiling aswell as both carts, one cc landing with a cart on her leg.
the pax held us down untill it became heavy jolts and we returned to galleys. in a mild state of panic. the aircraft leveled but because of the situation and number of a/c around us we had to maintain level and for about 1hr we were hittin lots of bumps some heavy enough for items to leave surfaces. it was extremely scary but i knew we were thousands of feet from the suurface but this doesn't stop the feeling that you are simply goin to fall to pieces in the air.
i can perfectly understand anyone's fear and exageration of something bad, (if you've ever been in an rta or air incident or anything for that matter) what does appear to be hours can be just minutes, but sometimes these things are prolonged.
due to current pattern over the atlantic a prolonged bout of turbulence is possible especially as the jet stream has move several times this year.
as or fd and cc, in my experience they strap us in far before we think we have to but this seems to be because they are aware that it's worst in the depths of the cabin than at the pointy end!!