I think it depends on where you live and how prevalent biking is. Commuting to work here is very popular. The commuter train in the morning has a lot of fold up bikes, road bikes, MTBs and plenty cycle to work in the city. Most buses here have bike racks. I don't think it's possible for someone to drive to work and home to and from here without passing dozens of bikers. All season, winter riding is encouraged here by all the bike shops. In the city I know of 3 custom bike shops, way out of my budget. $2K for a steel bike? No thank you, I'll build up my parent's Univega instead.

I use lights on both front and back regardless if it's light or dark outside. And for me what scares me most are pedestrians or young drivers. I've had stupid girls who can't parallel park just pull out right in front of me. I'm contemplating getting an airhorn just for the purpose of scaring the crap out of drivers who can't park and think it's OK to just pull out into the street without looking.
- Pedestrians I've noticed don't care about bikes. They care about cars. But if they see me coming down at 10-15 mph, they will still walk right in front of me, have zero concept that my bike can't stop on a dime, even if I did, my wheels would skid and still crash into them.

I think it's just safe to slow down, coast and be ready for anything whenever you pass a driveway or a blind turn. I don't ride to race. I ride to commute or to just enjoy being outside, so I'm not trying to bike at 20+ mph constantly. I average about 15-18 mph since I'm much more worried about cars, pedestrians, blind turns, driveways etc.

Cross fingers, I haven't had any road accidents. But I've wrecked an MTB before. My buddy also wrecked his MTB, a pedal, chainset etc. I've watched 3 people fly over handlebars head first. I've seen far more accidents and injuries on MTB than road. I think maybe that's because on road, you don't take risks and ride defensevily.