Not nominating the clear frontrunner is a big FU to the millions who voted for him. There will be long term consequences if it happens. But I don’t think it will.
Depends on how “clear” that front runner is at the convention. But never fear, if Trump comes up short on delegates he’ll use his magical deal making abilities to get the nomination. And what better way for him to win—that would actually unite the party behind him too. It’s probably best for Trump to get a contested convention. He gets to display his amazing deal making abilities and unite the party behind him!