I don't understand this part
Turns out Jeff was in on the attack (not just mailing letters) from the beginning, right? So why do we see about 20 minutes of movie events unfolding which show that all he planned to do was mail letters, and showing his complete surprise and anger at Shawn when he finds out what his hitmen did? Was all of that Jeff's version of the story? It wasn't clear, especially since in the end he did confess that he planned the attack, so why in the present day would he recount a story which is the opposite of what he confessed to, and why would the movie show us that story for so much of the running time? Or what am I missing?
Also, a side question... Why did Tonya's mother want to tape her?