(or "Engine Elasticity")
Everyone knows how the storytelling engine of the Incredible Hulk goes. There's Bruce Banner, brilliant-but-timid scientist, who's being chased by the hot-tempered, obsessive General Thunderbolt Ross. When Banner gets angry, he changes into the Hulk, a big, green, dumb guy with unbelievable strength, who smashes everything around him in a rage. (Which is, natch, why Ross is chasing him.) Meanwhile, Banner searches for a cure to his condition so he can reunite with his beloved Betty...who happens to be Thunderbolt Ross's daughter, in a classic case of divided loyalties.
Unsurprisingly, that storytelling engine doesn't actually show up as much as you'd think when you sit down and read the Hulk. Why? Because it's a terrible storytelling engine, that's why. It's a false status quo, for a start--Banner can't ever cure himself of being the Hulk, and Ross can't ever catch him, because either way, the comic would end. The Hulk is a passive character--not as maddeningly passive as the Man-Thing is, but still very limited in his ability to shape the storyline. He either wants to smash it, or he ignores it. Most Hulk villains have to essentially goad him into beating them up, sort of like a kid who throws rocks at a "mean" dog until it snaps at him. And there are very few easy story hooks in this engine--Ross is only interested in catching Banner, Banner is only interested in curing himself of the Hulk, and Betty...the less said about Betty Ross the better, but let's just say she won't be a spokesperson for the National Organization for Women any time soon. The stories using this engine quickly become repetitive, which reduces the interest of both writer and audience over time.
And yet, this is the model the Hulk always returns to sooner or later. More than any other series, the Hulk departs its own storytelling engine to build a new one; the Hulk gets smart, he gets pardoned, he goes into space, he goes into another dimension, he gets split in two, he gets cured, he becomes amoral, he becomes a member of a secret organization of immortal warriors and then goes into space...but always, it seems like we go back to "Hulk smash puny humans" sooner or later. Why?
Because, as stated in the opening of the post, everyone knows how the storytelling engine of the Hulk goes. The vast majority of Hulk readers, even true-blue comic geeks, are as familiar with the Hulk cartoon, the Hulk TV series, and the Hulk movie as they are with the Hulk comic (in fact, unless you're a devoted fan of the Hulk comic, you're probably more familiar with the TV series than the comic.) It's a repetitive formula that doesn't work very well over extended periods, but it's also an iconic, simple idea that makes a deep impression when you first see/read it. So while the Hulk engine has to stretch away from the iconic central concept in order to get room to tell plenty of stories, it inevitably "snaps" back to that concept, because it's what we think of as who the Hulk is. Even if a single writer swears they'll never go back to "Hulk Smash" stories, no writer lasts forever on a title. And sooner or later, someone'll come along who remembers what Hulk comics "should" be like. They should be about the Hulk. Smashing things. And being chased by the military.
And, of course, the magical purple pants that change size when he does.