If you ask me. The first time would have been enough for me.
But now this is what I see as reason enough to fire him/her...
1. 75 is plenty fast enough
2. That takes a deliberate effort to break what the company has determined to be a good idea.
3. What type of person will put that much effort into by-pass company rules (in this case settings)
4. What type of person does it again after being given a second chance and then again after getting caught a second time.
If you ask me, someone who either doesn't care or is too simple minded to understand. Either way, he/she does not need to be behind the wheel of a truck if you ask me.
Not any truck.
Those are the types of people who will then turn around and act as if someone did him/her wrong but doesn't look at his/her own actions.
I am big on second changes and allowing people an opportunity to make up for mistakes. I have made plenty myself. But this is not one of those types of situations.
What other policies, rules, shortcuts are being abused? It could lead to a terrible consequence.