Most drivers are—at least to some extent—confident in their ability to get behind a wheel, and manipulate their vehicle so that it safely moves from point A to point B. And this confidence is not a bad thing; after all, can you imagine the mayhem that would ensue if every driver on the road was riddled with terror at the prospect of sharing the road with other drivers and pedestrians? Indecision isn't exactly a trait that is prized for the promotion of safe roads. That said, however, there is a point where the confidence becomes something of an excess, and this is when we let all aspects of our driving become second nature to us.
The danger here is that when you are sloppy with details that you think only new drivers need to pay mind to, you are ingraining—both in your subconscious, and in your muscle memory—behaviours that leave you open to risks. For example, when you make a habit of rolling through stops, you may go through two years of doing this without the slightest bit of consequence; and each “successful” roll-through will just enforce (in your mind and body) that this is how you should be driving.
The problem is that when you finally do get pulled over, or do get involved in a collision of some sort that could have been avoided by making a complete stop and observing the intersection before you, simply resolving to “start driving better” isn't going to help you. By that point, your habits will be quite set, and it will take tremendous effort to reverse them. Sure, when you are consciously thinking about your driving, you may remember to come to a complete stop, but when your mind flits in and out of the road you're driving on, your body will revert to what it's been programmed to do over the years.
A penny saved is a penny earned, so doing your part to avoid increased auto insurance premiums makes good cents—I mean, sense. If there are techniques for safe driving that you learned in driver's ed but haven't been practicing, do yourself a favour and get your mind and body in training now.