Stephen Dixon is the most accessible difficult writer that I've read. He uses a simple vocabulary. The syntax is straightforward. He gets a little weird with timelines though, re-inventing a story sentence by sentence. In this, Dixon is the most like Samuel Beckett of and contemporary writer that I know. He doesn't really let his characters progress. They're stuck in their head worrying about possible eventualities, imagining what could happen, not necessarily what did happen. Also, like Beckett, his stories are simultaneously very sad and very, very funny.
In "I." we get a series of interlocking stories about a man caring for his ailing wife. Her disease is a debilitating one and as time progresses he must do and increasing number of mundane things for her: helping her into the shower, to bathe herself, to use the toilet. It seems to be a lot for him. He is prone to fits of rage that are more about his lot in life than directed and his wife and children. It's just that they happen to be around and end up collateral damage to his irrational anger.
"I." is bound as a novel, but because it's a novel composed of individual stories there's no plot or linear flow. Some stories seem to contradict each other. The wonderful opening story describes our main character (only known as I.) meeting a woman who we assume to be his wife. But the story is more about I.'s imagination, what he hopes might happen in his wildest fantasies. Dixon lets I's fantasies roam free. But even they are tinged with sadness.
The final story paints a different picture of I's meeting with his wife. But even after reading it we're unsure of what really happened to arrive at a meeting and a courtship. I. alternately imagines being introduced to her, gaining her name surreptitiously, orchestrating a chance meeting the next day, arresting her on the stairs, walking her home, hailing her a cab, etc. It's in these contradictory sentences that Dixon is most like Beckett. He's letting language cancel itself out. I. moves forward slowly, by inches. Some of his imaginings are funny, absurd. But Dixon has total control over what's happening.