Near the start (in the car with Jack McAlpin's photo file) Mulder refers to Private Jack McAlpine as "John".
The first scene with the agents and Mrs McAlpin has her saying "Jake used to tells these jokes..."
Thereafter the name "Jack" is used consistently by all.
At the start, Jack drives his car into a tree with such force that the integrity of the driver door is compromised. Yet the windshield remains perfectly intact despite Jack not wearing a seat belt. He should have gone straight through the windshield.