...would this not get tons more people out on the road making it even more congested.
I think that is a legitimate concern. But I speculate that when it comes down to it, maybe one in several thousand people who say, "Hey, that's cool! I wanna do it!" will ever actually do it. Three things will turn them away:
1. Time. When they realize that storm chasing is not a day-trip kind of thing, most people will concede they don't have [or won't make] time for it. Most of them won't even have time for a SKYWARN class.
2. Money. In addition to the work they're going to miss, they will also be quite dismayed by the costs involved. Most of them don't already have a laptop with ThreatNet, a Ham radio, or a gas card that somebody else pays for.
3. Difficulty. Once they realized that it's not as simple as listening to NOAA and then jumping in the car when the alarm goes off, most will drop out. And of those few who decide to try and learn a little meteorology will quickly say, "F this!"
I think it's like becoming a doctor or a fireman or a cop. Everybody who watches TV says they want to do it at one time or another, but darn few ever do it.