Thinking it over a little more, I think I see one of the problems here. I don't know how the video handles it all, but I think we're mixing issues when we talk about it being "dangerous to rush the shooter".
We've actually got TWO scenarios with a campus shooter, not one. Remember that. The first scenario is the one the first victims find themselves in. There's been NO warning - they're the first targets, and they're at the most disadvantage. Obviously, telling everyone in a packed room to up and "rush the shooter" isn't
necessarily the best advice. (Honestly, I don't know - I'm not anything near an expert!) Chairs are packed in together, and even *if* every single student immediately jumped up and attacked, it's a given that many someones are going to be injured, perhaps fatally. They may get the guy down, but the trick here is getting a bunch of people to rush him,
knowing that they run a huge risk of getting killed. In your garden variety college class, I'm not banking on that. I won't say it isn't a decent option, especially if there's no other exit. OTOH, if you're at the far end of a large room, you'd probably be shot before making it to the shooter. Ducking behind your copy of Shakespeare's Complete Works might be a smart idea, at least until something else presents itself.
If there are secondary exits, the safest course of action would probably be to run, escape, get out - as quickly as possible. Knowing, of course, that he's still shooting people. If you're by the door and can respond immediately to the threat, then an attack could be fruitful. Who knows. I have no deep desire to find out first-hand.
Any way you slice it, this first group is in deep, deep trouble, especially without a gun. *This* group needs a gun The. Most.
The second scenario is what everybody else finds themselves in, if they've heard any inkling of what just happened to the first group. These people - the ones in adjoining rooms, hallways, etc. - are out of the direct line of fire and have a chance to get away or make a split-second defense/offense/Nike defense plan. *This*, I think, is an easier spot for a plan of attack. If you can't get out of the area, plan to meet the shooter head-on. You (hopefully) have the benefit of surprise and a chance to grab a makeshift weapon. You've still got to be brave enough to face the risks, but if there's nothing to lose, you're in a better spot.
All that to say that, yeah, we need guns in schools...badly.