I’ve seen some terrific jumping WBs crossed w/ quarter horses in horse trials and eventing, and am baffled by the “mix that doesn’t seem to work” position.
If I had to guess, I’d say that it’s partly that quarter-horse people and warmblood people don’t rub up against each other much.
Warmbloods themselves, like quarter-horses, are ultimately a Heinz-57 of ingredients. The biggest difference is that the old-school quarter horse inspection was the quarter-mile race, or, at the very least, showing real cow sense in cutting and ranch work. With no inspection other than the show ring, many quarter horses have shed much of the functionality part of the breed requirements, and that can be worrying. For instance, through a chunk of the mid-late 20th century, breeders selected for giant muscles and tiny feet. The breed is still correcting for that trend.
Conversely, warmbloods cannot get into a studbook without at least one inspection, breed, DNA, movement, behavior, etc., and cannot reproduce without that stamp of approval. (A WB expert will correct me if I’m wrong.)
When I was in my 40s, I had a spanky cutting line QH mare with the dreamiest of extended trots and a guaranteed seven in her walk every time out. If I’d had a single brain in my head, I’d have bred her to one of the gazillion dressage-y studs in New England or anywhere.
The mythos around home-breds is palpable, so I’m far from encouraging more baby horses unless you’re committed to and have the financial resources for his or her entire life plan. That said, if you have a mare with things you’d like to mitigate, maybe she’s a bit too tall, or you’d like a more level-headed model of your mare with a splash of color, or versatility, or an actually lower head, why not use this stud? If you know him and have seen his line of babies, more’s the better.
While I have seen the look of incomprehension on at least one Hanoverian’s face when asked to help move some cows and the eventual light bulb over their heads when they get it, nothing will compare with my dressage-y QH’s first encounter with cows at age 26 when she suddenly had to share a between-the-fence water trough w/ a small cow-calf herd. She chased and turned those cows so hard, I was afraid they’d never get a drink. (They did. It was fine.)