It would probably be just as correct to title this post Block Made Easier, as I am not attempting a new defense of Professor Block's call for support of union thugs, but simply making an attempt to put the Professor's argument in a form that might be more easily understandable.
Suppose you are walking at night in Boston's beautiful Boston Common. It's late, and this being a public park, there is no protection in the park. As you walk down the park, you see two local thugs Scott and Union. Now Union is smaller than Scott, so he fights a little different than Scott but they are both thugs. Scott being bigger, meaner and tougher, he usually controls the mugging. You really wouldn't want to run into either one of these guys alone, but together, you are in double bad luck.
As they head towards you, Scott bursts out to Union, hey I'm sick of this 50/50 split. I want 80% because I am bigger and stronger, you can still loot but I am only going to give you 20%. Suddenly, they stop heading towards you. A fight breaks out between them. Do you root for Scott to beat Union instantly to a pulp? Of course not.
Once Scott gets done with Union, his next stop will be you. Since they are both thugs, you keep hoping that they keep slamming at each other. You kinda root for Union to get in a good couple of slams against Scott to keep the fight going. The last thing you want is for either to win because then you are next.
It makes no sense to hope that Scott beats Union because Union is a bad guy. I repeat, once they are through fighting, because of a truce or because just one is left standing, you are next on their radar.
Getting to the real world muggers in Wisconsin, Scott Walker and the government unions, Professor Block's great insight is that the union is the weaker fighter. Though they are instigators, unions have no power to tax, to set drinking laws, speed limits, permits, fees, launch grandiose projects etc. As Governor, Scott Walker has that power. You really want these two to keep on battling so that they don't have time to go after the innocent residents of Wisconsin. You want Scott Walker taking calls from real and fake Kochs, and spending the entire time discussing nothing but his battle with the unions.
In other words, if you are a resident of Wisconsin, or simply an advocate of liberty living anywhere on this planet, and absolutely hate the teachers union (as you should), you still want them to fight on and strike some blows against the more powerful Scott Walker. Let the union preoccupy Walker so that he can't come after peaceful, innocent residents of Wisconsin.
As Professor Block says, a pox on both their houses. And until that pox comes, a good long battle between the two will have to suffice.