The correct procedure for those whose piss is boiling at the sight of horses in the road is to screech to a halt just behind them, with the engine revving hard, and sounding the horn.
Good luck!
No difference at all - if somehow you haven't managed to notice that some roads are much wider than others, often with more than two lanes. If the road is wide enough to pass a line of parked cars without having to stop for on-coming traffic, it is wide enough to overtake a bike.
No you couldn't (apart from using the roundabout at motorway junctions, where mostly you still can). There never was any sort of right hand turn allowed on motorways.