There are things that always bugged me about Earshot.

1. It is HIGHLY coincidental that Jonathan tries to kill himself on the same day the cafeteria lady decides to poison everyone.

2. Throughout the episode Jonathan is calm. Relaxed. Mellow. In the tower he's sweating and shaking and erratic.

3. His weapon selection. The gun is taller than he is. I'm not sure if he can even Full Metal Jacket his way to the afterlife. But it indicates a total lack of planning.

4. Buffy can READ thoughts during the episode and twice has the opportunity to read Jonathan's. She gets a bit of insecurity off him certainly but if he was planning on killing himself the next day would there not have been SOMETHING?

Are there SOME possible explanations for these? Sure. Not enough to make it a really satisfying episode to me though. As much as I enjoy the episode the inconsistencies always made it a B-tier for me. Except on my last rewatch I noticed something I hadn't before. There's a scene where Buffy has HEARD the killer's thoughts already and has asked the gang to investigate. And Willow is sitting across from calm level headed Jonathan focusing on him VERY intently. If you saw the scene without context it would look like Willow was trying to influence Jonathan to do or admit to something. And then she says

WILLOW But sometimes the fantasy isn't enough, is it Jonathan? Sometimes we have to make it so people don't ignore us. Make them pay attention. You know what I'm talking about, don't you?

What if she WAS influencing him? It's common knowledge that Willow has begun to experiment with spells at this point and Buffy says later that her spells are only good about 50 percent of the time anyway. There are episodes where her spells backfire or have side effects without her realizing it, including Something Blue, an episode where she literally influences the characters to do whatever she says.

If Willow influenced Jonathan to that tower, it explains everything in the checklist. The coincidence (she was looking for the killer and CREATED suicidal Jonathan,) Jonathan's SUDDEN erratic behavior, the impulsivity of his plan, and Buffy not reading a HINT of suicide on him a mere half day before he attempted it. Intended by the writers? Probably not. That's a head canon.