Plaid with a regular suit?

[Jock Scot]

As you are asking and using your picture as the example then, DON'T DO IT, please! Unless you want him to look like an extra in a third rate pantomime.

Thinking on here, if it helps any. It is traditional (although not seen often here in Scotland these days) for the bride to wear the husband's tartan, in sash form, AFTER the wedding service.