I spent 12 months commuting from Brum to Manchester, as long as there were no accidents then it was a fairly smooth 75 minutes from front door to desk, any accident encountered though would push this time up , even now I commute from J10 to J4 and back each day, last Saturday it took me 2 hours to travel the 25 miles due to 2 pretty minor accidents on the M6.
A lot about luck it's fair to say and probably says more about our reliance on creaking infrastructure to get around where the slightest issues snowballs very quickly. The M6 toll by the way is a dream, if I'm aware of an issue prior to leaving work or home then taking the toll is the definite answer.