Something that I keep coming back to in my thoughts as I have followed this thread is that there are programs (in North America, even) that absolutely do breed an amateur friendly dressage mount, whilst being purpose bred, using quality stock, and still being affordable (caveat: I know affordability is a matter of perspective, but I am thinking of foals in the high 4’s or low 5’s). There are programs with SPS mares (sometimes generations of them), using top stallions (both NA and European bloodlines).
As I’ve seen one breeder point out: they do this themselves, they need to be able to safely handle their mares/foals during pregnancy, labour, and the aftermath - so temperament is of huge significance.
I guess part of me looks at elements of this conversation as “a solution in search of a problem”. I admit it - I was crazy dubious with the WB/iberian breed crosses but having watched them as they mature and come along, I can see where the cross offers some solutions for both parties - the warmblood can bring a different temperament to the table that the iberian breeds may benefit from, and can assist with changing the shape of the body just enough to improve on the canter and the extension, and the iberian breeds can help bring some reactiveness to some lines that may lack the responsiveness to aids, can also help with making the frame more compact in lines that have issues with a back that is getting too long, and increase the power for sitting and carrying.
The TBs and the anglo arabs were really promoted in the WB registries in “recent” history for much the same reason - there was a “problem” (type was heavy, coarse) and the introduction of blood was a solution. In the same way, appendixes make a lot of sense, along with some other more familiar crosses.
I guess I do not follow where the “classic” phenotype of a DHH (as, the breed standard) aligns with a WBx and what purpose it serves - couldn’t one go source a gelderlander/horse with gelderlander blood for this purpose, without some of the drawbacks of a conventional DHH? And at the end of the day, while one can say they have a DHH mare who is “not” average/the stereotype it still is never quite certain what crosses will pass on (why so many draftxTBs can be…interesting) - and sometimes, it seems like the introduction of an outside breed can really shine in the second or third generation, not the first gen crosses (though of course, this is not always the case!)
At the end of the day - there is a market for a safe, kind, forgiving, trainable, ridable amateur horse. I think you can also have a program that focuses on that without compromising on the quality of the horse, since so many of the colossal gaits are the product of tension (in worst case) or training/strength/strategic riding (best case). Perhaps someone may not choose to breed to (insert notoriously hot sire here), but for every (insert notoriously hot sire here), there will be a Romanov or a Belissimo that are just as qualified (no “compromising quality” at all) with a temperament that is more forgiving.
Wall of text. But wow this thread went places, there was a lot to ponder on.