It may seem like Jimmy was just being nice to Evelyn by not venting at her again for missing the cut-off man, but in actuality, he was just being a manager. One of the jobs of a manager is to adjust his coaching to players on an individual basis, and venting at Evelyn wouldn't help her. You'll notice she gets the message, and at the climax, she hits the cutoff man perfectly.
The awkwardness between Jimmy and Dottie before she leaves with Bob and when he later meets him makes a lot more sense given the Deleted Scene of Jimmy and Dottie kissing.
Crossing over into Fridge Sadness. Early in the film, Evelyn's husband forces her to start traveling with Stillwell, because he can't "read the want ads" and take care of the boy at the same time. Later, in the finale, a grown-up Stillwell remarks that Evelyn has died, but he made the trip to Cooperstown in her honor: "She always said it was the best time she ever had in her whole life." All of this suggests that Evelyn had an unhappy marriage—she's the only married woman we see (besides Marla) whose husband isn't at war, just out of work, and judging by how quickly he dumped Stillwell on her, he probably wasn't father of the year material. Evelyn was likely eager to stay out of the house as long as she could, and cherished her time with the Peaches more than her raising a family. This might even explain why Jimmy's yelling results in a teary-eyed breakdown: she might be used to her husband screaming at her for mistakes, and hoped to get away from it while playing baseball.
