I had two small "sewn eyelets" (sort of like tiny, round buttonholes) installed (installed? Well, you get the idea) in my dress jacket. Yes, they show when I'm not wering the plaid. But no worse than the "normal holes" would.
I considered wearing the broach (I wear a pennannular)w/o the plaid once or twice (haven't actually done it, though). It would "fill" the holes...And I'm not quite sure how silly it would look. Ham? Care to weigh in on this one?

Hal