Another great example is the difference between Rugby Union and Rugby League. While there are lots of rule differences, a key one for me: in Rugby League, defen

Another great example is the difference between Rugby Union and Rugby League. While there are lots of rule differences, a key one for me: in Rugby League, defenders must go back 10m after a tackle, while in Rugby Union they do not. This leads Union to be a very close affair with play rarely moving without consistent strong effort, while any fast player in League will get at least 5 of those meters back after every tackle. Very different games strategically, while from an outsiders perspective they are just the same.