When the celebrated Georgette Heyer discussed her heroes, she was clear that she deliberately put them into two categories, effectively alpha and beta. Beta heroes - Gilly, Freddy Standen or Gervase Frant - are generally easy-going, quietly-spoken types, usually humorous and sometimes shy. Their alpha cousins, on the other hand, are far more dominant.
Authoritative, powerful and demanding, the alpha men of Heyer are unmistakable, yet they always retain humanity. The Marquis of Rotherham is saved by his sense of humour, laughing when told, "you ain't done very handsome yet!", while Lord Worth is left staggered when Judith effectively compares him to her father.
However, we are not all Georgette Heyer. And when it comes to the domineering, alpha heroes, there is a question: how far is too far? Where does a hero cross the line in dominating the story? Is there a line to cross?
Interestingly, Lord Worth stands accused in several online forums of crossing the line because of the scene where he picks Judith up and kisses her against her will. According to one poster, this is sexual assault...which it may be today but certainly wasn't in 1810, nor when Heyer wrote it. Arrogant as Worth is, he gets a hard smack for his trouble and he never tries it again. Alpha, yes. Over the line? Not in my book.
Outrageous as some consider them, Worth's actions pale alongside some of those offered by apparent 'heroes', some of them in books astonishingly still published today. This is not Fifty Shades I'm talking about either; Christian Grey is not a hero, he's a damaged, abusive anti-hero but that's made plain from the start. Try instead the repulsive 'Emily' by Jilly Cooper, where the nasty little leading man rapes the heroine. She then marries him and he makes her miserable but hey, it's ok because he paints a picture of her at the end looking 'incredibly sad'. How sensitive of him. Mid-18th century one might expect something like this, but from the 1970s it's particularly vomit-inducing. And, of course, he is not a hero because he is a rapist. There are unfortunately a few books with this premise, but romances, they are not.
What other disqualifications are there? It depends. It depends on the skill of the writer and the character overall. After all, a lying would-be bigamist doesn't sound that great but Mr Rochester overcomes it. In Regency times, a few slaps could be traded by both without the horror it might arouse today, and you may well find that in modern depictions without losing faith.
Back to Heyer. Back to the idea of humanity - because when the hero loses that, he's no longer a hero either. The male character in Emily has no humanity for obvious reasons, but there are too many novels where the super-alpha male is a crushing, domineering, suffocating dictator whom the heroine incomprehensibly loves because why on earth would you love anyone so appalling? Someone so controlling? Someone who cares so little about you that they will trample all over you?
That is not love. That is not human. So that is not romance. And so that is when the domineering hero has always gone too far.