My commute is between 1 to 2 hours depending on the day and time and I am only traveling 40 miles. I'd rather take a train for two hours seems certainly doable.
You have to get 45 minutes earlier at the station for passport and luggage control. And you also have to factor the time to go from home to St Pancras, and then from Gare du Nord to your office.
Practically, it's a way longer commute.