These thoughts have crossed my mind countless times before. I can recall two Thoroughbred mares specifically who had not been successful on the track and who were brought back home to be used as broodmares because of their great bloodlines. The one mare was actually very good looking (otherwise) but had very crooked legs. Perhaps if you bred her to something with very correct legs you could get a nice foal, but I wouldn't be trying more than once if the first foal turned out with crooked legs. To breed her once even involves quite a bit of contemplation. The second mare had extremely light bone (so light that she obtained fractures from light training as a 2yo) and was fraught with conformation flaws - she was not built to last whatsoever. But, she had great bloodlines so her owners were taking her back home to breed her. This occurs throughout the equine industry, individuals breeding a horse based almost solely upon bloodlines (or "well we just want to have a little baby foal around!"...but that's another maddening subject altogether). Is this line of thinking successful? Or does it simply add to an industry already teeming with too many horses, many of which possess conformation worthy of banging our heads against a wall? What about all those grade stallions? I'm not referring to those bred with purpose, some of the successful sporthorse or warmblood crosses, for example. What about all those grade mares being bred to another breed not within their breeding already? This is not to say either that grade horses are not valuable - to the contrary, I find them extremely valuable. Most of our sporthorses (or other breeds) even are not the result of one breed being bred down through centuries (such as the Arabian or Thoroughbred), they're the result of careful mixing of a number of similar breeds to create the ultimate sporthorse. Belgian/Quarter Horses, Percheron/Thoroughbreds, Friesian/Thoroughbreds, all are fabulous crosses with great potential. But cross-breeding should still be done just as carefully as breeding within a breed, perhaps moreso because of the risk (breeding two breeds of two different backgrounds, thus there is some unpredictability) and so grade stallions and grade mares being bred...does not seem to ring well (as a whole) to my ears. They are also less valuable within the industry, and thus usually start out near the bottom. Add to that poor conformation and poor performance and the horse is most likely destined to exist at the bottom of the pile, one day ending up in a truck headed to Mexico. Keep in mind I am neither referring to the individual who breeds one or even a couple horses for their own purposes and breeds with responsibility and caution, I am speaking in general.
Another off-topic point, is why it is cheaper with some stallions to breed a grade mare to that stud? Why wouldn't you instead be encouraging the breeding of purebred mares to a particular stallion over grade mares? Just a thought and perhaps there is a good point for this, I just have yet to find it and was unsure as to the reason. Certainly breeding grade mares to a quality stallion can produce some amazing get, however the risk is higher at obtaining a quality foal and thus very careful planning is required. I find that those wishing to breed grade mares are often of the type that are not looking to improve a breed or produce a quality foal, but are rather simply looking for a pet foal, a foal for their kids to grow up with, a foal to entertain them for awhile. Of course this is not always the case and sometimes it is it even turns out well, but it seems to often be the case, the result is often negative, and so it makes me wonder why stallion owners would encourage this. Like I said, just another random thought to consider.
Taking a break from this whole breeding buzz...it could be so much more in-depth even lol.