No it isn't, look at the bridle of the 2 horses and they are different, the one in the parade and the still photo of the galloping horse in Joe is post in the previous page. I'm no expert but I rode a lot when I was young, grew up on a farm with 50 horses operating a riding school did some competition but traded the horse early teen for motocross but, followed my sisters often to watch them compete. ( they won every thing in Canada as Junior.)Do we know if the above white horse that ran through London is the same horse as the white horse below?
I was thinking as you that they were the same horse until you brought it to my attention that they may not be the same. It took me less then a minute to realize that they were not. Look in particular to the martingale, the piece connecting the bridle to the chest. In the parade it is a chain and on the photo is of leader. I first thought that it was broken in the parade as it didn't prevent the horse to lift it head but it seem that it is maybe only decorative as it doesn't. So I stopped my analyzing the horse in the parade and it rider then as it is obvious a different one.