Character Analysis
Model Students (By L.C. Standards)
These two are the quintessential Executives. They're smarter than S.Q., which is a good thing—Mr. Curtain would be in trouble if all the Executives were like him—but they're not nearly as smart as Martina, which is also a good thing for Mr. Curtain. He'd be in even more trouble if all the Executives were like her. There would be dissension in the ranks as all of the Messengers and Executives tried to claw their way to the top.
But no—Jackson and Jillson are neither particularly dim nor particularly bright. They're smack dab in the middle of the bell-curve, average as can be (as their names, essentially Jack and Jill emphasize), and they're obedient, appropriately condescending to students of a lesser rank, and willing to carry out orders without question. What more could a power-hungry control-freak want in his underlings?
Special J (&J)
One reason Jackson and Jillson are especially good Execs is that they were both special recruits. S.Q. spills the beans on that little factoid when he's explaining to Reynie that, "special recruits get extra attention in the early days, by order of Mr. Curtain. They're a little slow to come round […] but you watch, one day they'll be top students. Special recruits often end up as Messengers and many become Executives" (13.38). Why? Because, as the MBSers realize later, special recruits are kids that have been abducted and brainswept.
But as Reynie points out, "because they weren't completely brainswept […] they aren't sad" (21.88) like the people whose memories are totally wiped (case in point: Milligan). And that "makes them better Executive material" (21.88).
The Future According to L.C.
So Jackson and Jillson are middle-of-the-road kids who've been subjected to Mr. Curtain's selective brainsweeping and retraining program, which means they give us a pretty good picture (though not a pretty picture) of how most people would behave if Mr. Curtain's Improvement ever came to be. They're his ideal minions, and that's what he wants the entire population to be. Eek—it all kind of makes us want to turn off our TVs, radios, and cell phones just in case.