Do you think the taser was appropriate?
I don't think any police action was necessary in this instance. However, they felt physical intervention was necessary and once that started the youngster should have just went along with them.
I usually come down on the anti-taser side of things. They scare the crap out of me and they're potentially deadly. Rare, but it can happen. However, in this instance, it seems appropriate.
The youngster had his hands under him it seems. LawDog addressed this on his blog this evening and when a person is in that state you can't tell if they're going for a knife or a gun. They aren't getting up off the ground until they're cuffed according to the 'Dog, and if LawDog says that's the way it must be then I'm OK with that.
Now, that said, I do have some experience trying to break a grip when folks are in such a position: About 9 years of wrestling. Ain't gonna happen easy. The 'smart' way is to peel somebody's thumbs away from the grip. This will involve an officer reaching under the nimrod and I can see why they wouldn't want to do that in the interest of officer safety.
Trying to break a good grip is going to take some force. Rough guess, back when I wrestled at 145lbs it took around 300-350lbs force to break a good grip with guys my size. The only way to do it was with the legs, and it took both of them. Now, how on God's green earth those officers are expect to do that, in that situation, is beyond me. There just isn't enough room.
The third thing you can do is going to be painful. Officer gets on top, drops his elbow into the youngster's shoulder, slides off to the side, snakes his arm under the youngster, puts his wrist about under said youngster's, grips his own free hand, and uses his arm like a lever. Something is going to give, eventually. I can see why this isn't on the police officer's list of things to try.
The fourth, a variation on the above, would be placing your elbow closer to the spine and pulling up and across the body. Useful in wrestling as it will expose their back to the mat. This could have been used to turn the guy, expose his grip to the police, and another officer could have broken the grip. However, I have personally witnessed somebody's ribs being dislocated (separated from the sternum) while doing this.
So, yeah... taser him.