Wow it amazes me at how mis-informed people are about what a warmblood actually is. Maybe try looking into the stud book information. There are incredibly strict guide lines for WB societies, particularly the older breeds such as the hannoverian. Most definitely not just a case of chucking a thoroughbred over a draft!
Yes, some WB's ARE overpriced because of the warmblood name. But this is on a smaller individual scale. Just like in any breed, there are going to be the 'duds' which the owner tries to sell for big dollars because of the breed and try to suck in unsuspecting buyers who are keen to be able to say 'I have a WB (or whatever other breed it may be)'. But overall, as has been said numerous times on their thread and many others I'm sure, a well bred warmblood, bred specifically for a certain discipline will be sold for a high price because of the phenomenal cost of breeding that horse, training it, registering it and competing it.
As for the Wb's vs. TB's discussion. Well I've had a few of both. From what I've seen, those who refer to Wb's as 'dumb bloods' do not have the skill to ride one of these horses, and need a more 'electric' type that will react to a more 'dumbed down' aid. I do find it amusing when people refer to them as dumb bloods though, when the vast majority of horses competing/training at Grand Prix dressage level are Wb's... how many Qh's, Tbs, paints, x breeds etc. have you seen doing GP dressage SUCCESSFULLY?? Not many I'll bet, not compared to how many WB's there are! This is because the Wb has been bred to have the brain and build for the higher levels of dressage. The Wb will think about a problem rather than just go off it's rocker like many a tb will when faced with a problem. Many horses will not go past medium level dressage because it fries their brains. But these horses are supposedly 'smarter' than a 'dumb blood'?? Go figure...
How the WB is built also needs to be taken into consideration. Yes you can do a reasonably dressage test on just about any breed of horse, no problems at all, you can train them a bit of lateral work, they can go on the bit and get a little collection. But unless the horse is built to carry it's weight over its hindquarters it is not going to cope in the higher levels. WB's have been bred to cope with collection, but also having the stamina to work with extensions as well (the Iberian horses are GREAT at collection but not so good with extensions, so this is where the WB has become the more successful dressage horse).
Tb's are not built to sit on their hindquarters and 'dance'. They are built to move flat to the ground to run as fast as they possibly can, using the forehand to steer and power on. A WB on the other hand is built to use the hind end to steer and for power ;) (trying to put this into simple terms!). Yep, there's some 'freak' tb's that can give a reasonable wb a run for its money, hell, I'm pretty stoked with my current horse who is a TB, he's VERY solidly built, he's up hill, short backed with a lovely sloping shoulder and already showing a talent for collection. But you don't come across many like that.
This is the same argument as say putting a draft horse or arab into a western pleasure or reining class per say. The Qh people would be fighting tooth and claw that their humble little QH's are the champs out there because they have been PURPOSE BRED. Exactly the same with the Wb's ;)