FMIL is convinced that if she doesn't write something about "casual dress" on the evites for our RD, that everyone will get all dressed up and then be upset when they find that the restaurant is totally casual. It's a tapas restaurant with kind of an island theme, and we have a private room, and I know some of the ladies will be wearing dresses, so it's not like dressing nicely would be widely out of place. I know FMIL will probably tell her guests by word of mouth, but I don't really want any kind of dress code going on the evites to the rest of the guests.
I keep telling FMIL that the formality of the invitation (lol, it's an evite) and conveys the formality of the event. So my question is...when you look at this, would you assume it's an informal event? Is there some appropriate way to convey this without dictating a dress code?