Correct Sir! Overtaking from the left is prohibited, but in a country like this where just a few sensible people give way, sometimes overtaking from the left has to be done, otherwise you can honk and flash your dippers all night&day and you will still be the one behind:)
Source- Sargodha road at night- Too many tractor trolleys Over loaded with sugar cane moving at 7-10kmph and do not expect them to give way:P Same goes to trucks etc.
Yes, do use common sense. If the vehicle ahead seems like it is trying it's best to let you overtake, be patient. Don't go all Hulk mode....
Patience is a virtue in itself!
Honda wala probably was driving faster than usual and tried to Zig Zag it's way through traffic... just an assumption!