Strict application of "modern doctrines" would have knock-on effects.
You'd have to say that Saher de Quincy-226 was succeeded as Earl of Winchester by his granddaughter Margaret, her father Robert having died vp, and then the title passed to her descendants the Lacys, who would be earls of Winchester as well as Lincoln, without ever knowing it.
Meanwhile Roger, usually called the 2nd earl, would have to be the 1st earl of a 2nd parallel creation.
Then you've got Isabel de Warenne, "4th Countess of Surrey". Her 2 husbands are normally called the 4th and 5th earls, and the next one the 6th (though not on Wikipedia).
If the 1st husband had left a son, complications would have set in, and even more so if he'd left a daughter.
Trouble is, nowadays, a peer's wife is a peeress, but the husband of a suo jure peeress gets nothing - it's totally sexist. And the law has never been changed, from which it is now forced to infer that there was never any such thing as a title in right of a wife, in the face of all the evidence that there was.