Eh, rules are meant to be broken. And keep in mind these are at best European rules -- and even then, certain areas (England!) took them more seriously than others.
There's also a lot of rules lawyering possible. e.g. red doesn't touch black on the German flag, because that would violate the first rule; instead, the field (background) is half black and half gold (color touching metal, fine), and the red stripe is on top of this field, totally legal, wink wink.
That said, trying to follow these rules has led to some strange decisions; e.g. it's interesting to look into (some unverified stories about) why the US flag has white (silver, metal) stripes on a red background, while the US seal has red stripes on a white background.
I thought that red didn’t touch black in the German flag, it touches sable, which is a fur. And furs can be placed on metal or color. … yeah, rules lawyering.
There's also a lot of rules lawyering possible. e.g. red doesn't touch black on the German flag, because that would violate the first rule; instead, the field (background) is half black and half gold (color touching metal, fine), and the red stripe is on top of this field, totally legal, wink wink.
That said, trying to follow these rules has led to some strange decisions; e.g. it's interesting to look into (some unverified stories about) why the US flag has white (silver, metal) stripes on a red background, while the US seal has red stripes on a white background.