Safe places to overtake cyclists include:
-straight road sections
-wide road sections
-corners if there is good visibility
Places not to overtake cyclists:
-roundabouts
-sections of road with solid traffic islands making the lane narrow
-when the cyclist has their arm out indicating they are going to turn right.
I'm a driver (20k miles a year, so pretty experienced) and also a road cyclist.
If I'm trying to navigate any of the second set of circumstances I will ride bang smack in the middle because impatient drivers don't leave enough room. I will pull in closer to the kerb in the first set because ultimately if a car is ahead of me it is highly unlikely to hit me so being overtaken is preferable.
I can clock 5 or 6 mph quicker average cycling to work on the road than on cycle paths because they are straighter, the surface is better and I don't have to keep stopping and unclipping my pedals for aunt Mabel, her dog on a flexi lead and her 5 year old on one of those wiggly scooter things.
Maybe everyone who passes a driving test should have to do 20 miles round A and B roads on a bike...