There’s another usage for H-Bomb. I have a couple friends who went to Harvard and they used to joke that when they were hitting on girls in bars, they always kept the H-bomb in reserve until they needed it. Then, if they really wanted to impress the girl they’d drop the H-bomb on them.
Another version I’ve heard has the exact opposite meaning, i.e. when you tell people you went to Harvard — i.e. drop the H-bomb — they think less of you.
To be fair, when I worked as a public television producer, a few of us would joke about hitting on girls in bars and playing the super-sensy (i.e. super-sensitive) PBS polar bear and navajo rug-maker documentary card. “Oh, she seems pretty liberal, better put on my PBS cap and talk about filming kittens affected by global warming…”