Dan Mathews leaves his office driving a Buick but arrives at the scene of the crime driving a Pontiac.
Exact height to within 1 inch cannot be deduced by a shoe impression. Weight could be estimated, but only after doing an on-site comparison using the same soil with a known weight for comparison.
Police work in shifts to provide 24 hour coverage. Supervisors such as Mathews would not work day and night as shown unless it was an extremely high-profile case such as an officer being killed. The theft by deception from the supermarket would not qualify as a high profile case warranting overtime.
The fake armored truck and the real one both had the same license plate.
Early in the story Dan Mathews steps out of his office and talks to the Sergeant sitting at his desk. During their conversation the clock on the wall reads 1:29 with the second hand stuck at 20 seconds.
After learning about Denson via his shoes, the same footage from earlier when Mathews went to the body shop is used- the police car at high speed turning off the road by the gas station.
By breaking into Burns's garage without a warrant Matthews guaranteed that all the evidence inside would be inadmissible in court.
A main point to the plot was the recent purchasing of sheet metal by the body shop that lead to the shop's owner. The armored car as shown was a standard panel delivery van that would not have required any added sheet metal to modify- metal would have been removed for the small windows and gun ports. While Mathews had asked about bulletproof glass, which would have been a required modification, that item was not mentioned when the reports were reviewed.
After he puts the money away, Art tells Kay that due to the money she won't have to wear last year's dresses and waves his hand at her outfit. She was wearing a blouse and skirt, not a dress.