Ethics and courtesies of branching into other tartans?

[Tomo]

If you like a particular tartan, ultimately there is not much stopping you from wearing it.

Just go for it.

Whilst my personal preference is to wear something I have a connection to I would not object in the slightest to anyone else wearing the same tartan for whatever reason - or even ask them about it, let alone challenge them on it.

I have 3 kilts in different variants of MacFarlane tartan, plus 2 ex-hire kilts I purchased mainly for when I am doing guided-tours in Scotland to avoid to avoid hard wear on my other kilts (one is a house tartan the other in Scottish Rugby tartan).

Next on my wish list is weathered Douglas. I have no obvious connection to the clan, although both sides of my family (at different times) came from Castle Douglas.