Indeed get your car 1 foot ahead of the other car, engage indicators and you have right of way.
To be honest YES thats how it works in the Danish traffic code, but the way people speed up from behind with clear indications that the 2 or more lanes are becoming less lanes now, that i am sure was not the intention with the law, cuz this way people are just creating congestion and not least dangerous situations.
Merging are most times in behind another vehicle, but if before that you accelerated to get in front of another vehicle, and then force that to brake "hard" to let you in, well then in my book you have failed, and you have earned the douche label.