More questions, if I may...

I see examples of the baldric being worn over the waist belt, as well as examples of it being worn under the waist belt. This portrait is a good example of them being worn differently:



By far, it seems the most common style is to wear the waist belt over the baldric, which I assume is more practical to help stabilise it and keep it from swinging. Is either way more 'correct', or is it just personal preference?

And on a similar note, I see examples of the baldric being worn both over and under a plaid. The example I just showed, as well as several other examples in this thread, show it over the plaid, and this seems to be the most common. But OC Richard's personal example shows him wearing the baldric under his piper's plaid, and I have seen a few other instances of this as well. So again, is one way more 'correct' than the other? Or do the rules vary, depending on whether you're in the military, or a piper, or something else, or is it just down to personal preference again?