I only recently started having blackouts and they scare the hell out of me. First of all, the fact that I started having blackouts drinking the same amount that I always did without blacking out in the past makes me fear alcohol has damaged my brain. Plus it's scary to have someone tell you things you did when you were completely alert, coherent, making sense, and not even necessarily appearing drunk, that you have ZERO memory of.
I did some research into alcoholic blackouts when I started having them and there was an analogy that it's like the video camera is on and running (the video camera being our brain) but there is no tape (or SD card) in it. This study researched how it was possible to have a coherent conversation if there was no memory and they found the short term memory would last something like 1 to 2 minutes, which allowed the person to communicate but the "data" was immediately discarded.
For me blackouts are scary and horrible and definitely not intended.