IQ considers what people are really driving on roads, not the posted limit. However, only the default speed imbedded in the map for major roads gets shown, not what IQ data shows.
I mean, you could do the math I suppose....
For example, let's say the time for fastest calculation shows 5 minutes. Activate the IQ routing and the same route might show 4 minutes.
So, if the distance is 5 miles, then non IQ speed = 60 mph
IQ speed would be 75 mph according to its data).