cool thread (and blog post!) thanks stacey!
I went to a dressage show a few years ago in the Atlanta area, at Chateau Elan, and there was a woman there riding a Percheron/TB cross who I think showed PSG. One of the upper levels for sure. He was a really lovely gray gelding who looked like an old type European WB. Maybe someone from the Atlanta area knows who that was. I always regretted not writing down the pair’s names so I could follow up on their career.
Not sure if my guy qualifies since he is part Warmblood, but I have a pinto Friesian/Warmblood cross that just debuted at Prix St George. Don’t have the rides on Youtube, but I have video of him schooling various upper level movements - search for MysticOakRanch for various video clips. He’s only been in dressage training a few years now 
And a while ago, I had seen video of Cardi (the Welsh Cob) doing PSG - it was on youtube. And Hilda Gurney was riding a NSH (Arab Saddlebred cross) at Grand Prix a couple of years back. And there are a few other Arabians and Morgans out there doing at least PSG. Last year, at the local CDI, someone was showing an Irish Sport Horse at PSG. And of course, I bet we could find some Andalusians and Friesians on Youtube if we looked. Dressage is definately not limited to the Euro-Warmbloods:winkgrin:
Balagur - Russian trotter
Balagur performed in both the 2004 and 2008 Olympics. He received a perfect 10 for his piaffe in World Cup Competition. He raced at two and was a mounted police horse for ten years before he was “discovered” and trained for dressage. http://www.youtube.com/watch?v=SaiVtHS6VrI
I don’t have a video clip posted yet but should be able to do so this weekend. However, my 10 year old welsh cob has competed a handful of times at Prix St. George at both schooling and recognized shows. We actually made our debut, if you will, at a recognized show this past weekend winning our first Prix St. George class with only a 62.7% but I’ll take it. (There were 2 other amateurs and 2 open riders on warmbloods that we bested. I must confess though that the two YR’s riding PSG who did receive sl. higher scores 63 & 64% I think but we’re talking quality horses that are way out of our league.) Not only is my guy not a warmblood but has rather challenging conformation that he must overcome to do the job. His heart however is endless which is what has made it possible. We even received 6’s on all but one of our canter pirouettes over the weekend from both judges so I certainly consider it a minor victory. We show again at another recognized competition in a couple of weeks.
So while I will work on getting a video posted. Here is a link & directory directions to the pictures that the professional photography got of one of our tests. Hopefully it will work.
http://www.seanbucknerphotography.com/gallery.php & go to Dressage Shows >>Tucson Dressage Club >>TDC March 2009>>Saturday 7 AM - 10 AM >>Page 34 (we’re the chunky monkey bay)
My trainer has one of these cobs from Madoc Farm and competes him Grand Prix. He may be the one you’re thinking of from young riders, I think she competed him there as well.
How about a 15.1 hand Morgan cross that does Grand Prix? Showed at Devon last year.
http://www.youtube.com/watch?v=AN4ALWSuUjA
Oh, and the cross is NOT warmblood. The dam was a grade horse that looked like a TB.
this site has several non-WB upperlevel videos, including Stravinsky a Polish TB at PSG:
http://behindthebit.blogspot.com/2008/04/non-warmbloods-in-dressage-breath-of.html
Courteny Fraser is quite a young legend in my area. Used to watch her all the time when she entered our local shows.
Check out Cardi and Jessica -
http://www.youtube.com/watch?v=Is4SpBp5aAU
http://www.youtube.com/watch?v=I9w59hvGZUg
http://www.youtube.com/watch?v=nLM_1MXjp1o
Cardi is just as wonderful in person.
OMG!!! I LOVE Cardi!!! I need to have Cardi!!! And I REALLY want to ride with Debbie! Those were great vids.
Here’s Ta’ez, an Arabian stallion, performing a GP Freestyle in full native costume. Fun stuff! Ta’ez is the 2008 Arabian National Champion Grand Prix & Champion Freestyle.
http://www.youtube.com/watch?v=NEKoSoWF4mE
http://www.youtube.com/watch?v=hrhLRs7AqEo
