Should a guy be scared of sex if he is at an average size?

Not at all! Average is the best size, not too big not too small. It works perfectly.

don't be scared an average size is best!

Sorry, but an aveage size guy just doesn't do it for me. I vote no. There are plenty of girls who are satisfied with average though so you shouldn't have any problems.

An average sized guy should do fine in bed...that's what most girls like

Heck no he shouldn't be scared! Average size is just fine... maybe even perfect. A girl is more interested in the guy and everything else about him. She's not thinking about his size until she gets to that point. There's a whole LOT of ways to please a girl in bed and out of bed besides trying to impress her with an "above average" size. A girl can receive only "so much" pleasure from size. But she can receive "much" pleasure from everything else he does. Now I'm talking about a guy that has at least "average" size or close to it. lol!

yeah most of them prefer average size. trust me, I'm girthier than average, and it does me no good.

Most women I know prefer average and down. A hit on cervix is usually enough to break the spell of mighty dong.

Relax. Learn how to use your mouth and your hands well and she will be more than happy with your **** when you get to the f***ing.

You asked the question two ways. The answer to the first one is no, the second yes. It's the same answer though: An average sized guy, with the right mindset and effort, can please a girl just fine. Maybe even better than someone super endowed, because it's about everything that goes into the act of sex, not just what goes into the girl.
Focus on making it passionate, and respond to her signals about what feels good and what doesn't. Relax, enjoy yourself, and you'll be just fine at developing the skills for great sex.