Interesting theory, but I've heard the opposite too...that late bloomers tend to have better sex lives. It's hard to interpret data for things like this.

They're still being virgins have be indicative of personality difficulties rather than sexual desire.

I bet there is hardly a male or female who would not be apprehensive about loosing their virginity, even if for very different reasons. Those that can separate the act from love would find it a less traumatic event long-term. Falling in and out of love is more difficult than the physical act.