Wideawake, I love the way you think!
I was just thinking about this today, and I realized that one of the basic assumptions of the anarchist/Black Bloc movement is an anonymous solidarity.
They assume that they will just show up in a town they may have never been in before, and will hook up with hundreds of people they've never met and that the whole group will magically think as one and act as one without having to do much prep or much vetting.
Now look at our window-smasher. Now that he has wounded himself and requires serious medical attention, the likelihood of him ever taking "direct action" again is small.
Think of it psychologically: he was elated and euphoric about his feelings of power and camaraderie and anonymity one second, and then a few minutes later he was lying on the ground in a pool of his own blood and likely fearing for his life.
In his gut, from now on, he will feel deep aversion to repeating his experience.
Now imagine a scenario in which people who feel elated about protesting and are reveling in their anonymity and camaraderie and power - and then one or more people in their little group turn on them.
Push them around, strongarm them for a dubious loan or donation, rip them off, taunt them for lack of sufficient radical commitment, claim to have photographed them breaking the law, ask them what they are willing to do to not get turned in, tell them that a trusted cell leader or organizer said they were an easy mark, etc.
All of a sudden those positive feelings of elation will be gone. They will no longer feel powerful, because people they thought were brothers-in-arms were ready to prey on them. They will no longer feel camaraderie when their comrades are mocking them or intimidating them or shaking them down. They will no longer feel the safety of anonymity because they know now that people in their own group may be watching them.
Their really cool protest trip turned into a major downer, something they don't even want to think about.
If the larger organization realizes they are being disrupted, they have two options - either really vet their operatives minutely and thereby diminish their effective numbers, or reduce the operational preknowledge of their members even more, and thereby dilute the effectiveness of the operations even more.
And it would be fundamentally asymmetrical: conservative protestors do not come to violate the law and do not protest in disguise.
More importantly, conservatives do not draw their sense of self-worth from the act of protest. For conservatives, it is an expression of opinion - not a way of validating otherwise empty lives.
Just some thoughts.