The RRLLR combo is standard for a road race (Even monaco has the bus stop), they place these parts of the track to slow the cars and allow cars to close up without possiblity of overtaking, try to make things safer I guess. There musts always be overtaking oppurtunites on courses, of which there are many on this track, but there also has to be a single race line part where cars must filter though, otherwise it's simply mayhem!