To judge this, consider how much time will saved. In dense traffic or if you are about to turn left very little time is saved by overtaking.
Is it Safe? First assess the comparative speed of the vehicle to be overtaken or of oncoming traffic and your own rate of acceleration. Only if you are certain that there is enough clear space ahead to enable you to regain your position correctly without causing danger or inconvenience to any other driver, is it really safe.
Overtaking on the left is permissible only
When you are turning left at a junction.
When the driver ahead has signaled his intention to turn right or has taken up his position to do so.
In traffic lanes when vehicles in your lane are moving faster than the ones in the lane on your right.
Procedure for overtaking
Check behind in your mirror.
Check the distance seen to be clear ahead.
Change down if necessary for peak acceleration.
Check behind again in your mirror.
Give a signal of turning right.
Overtake leaving a good margin.
Check behind in your mirror and take your correct position when it is clear-- don't cut in.
At night, never dazzle the driver in front through his mirror or those proceeding in the opposite direction. The use of headlights is prohibited in Bombay.
Don't over take.
From the left except as explained
By weaving in and out from one lane to another.
At a pedestrian crossing or when pedestrians are seen crossing else where.
At a road junction
At a bend or corner
By crossing the continuous white line painted along the center of the road.
On a humpback bridge.
Where the road narrows.
At a level crossing.
When the road ahead is not clearly visible.
When there is a sign prohibiting overtaking.
When you would cause another vehicle to slow down or swerve.
When you are in doubt.
Stay in touch
Office of Senior Superintendent of Police New Court Complex, Kartarpur Road, Kapurthala
ssp.kpr.police [at] punjab [dot] gov [dot] in firstname.lastname@example.org