Some advice sought please - re both tartan ties and hose.

I frequently see advice that one should not try to match one's tartan tie to one's kilt - is that an absolute no-no? It looks OK to me - so why is that advice so frequently given?

Second - many clans have a variety of choices for kilts - my kilt is Campbell of Argyll - which to clan purists is somewhat beyond the pale. (It's a long story). Were I to buy a second kilt I'd just get a Campbell. But years ago, as a guest of my Chief, it was clear that he had bigger problems to manage.

Would wearing Campbell hose look awful with it? Of course, in portraits done of Highland chiefs a few centuries ago they'd mix a variety of tartans - should one avoid that now completely? I have seen a modern clan chief with one tartan for his kilt and a plaid in a different tartan - both "correct" but different. What are the views of forum style experts?