though the video is called "sparring" it's not really sparring. they just work on different strikes, the interesting thing is that you never see them in the same ring together. in this video you do. surely they also sparr, but behind closed curtains. here is the link: http://www.megaupload.com/?d=ABIVI9QD
I doubt the Klitschko brothers spar, even behind closed doors. I wouldn't spar with my brother, it's just a stupid way to create unnecessary problems.
I think they used to spar together until one of the broke the other one's arm. Then they stopped sparring.
it would be logical for them to spar, but only to a certain extent, maybe at 50% without powershots. but i agree that it could create problems in their relationship.
This Video is very old. Both were boxing for Universum. Now Wlad trains with Emanuel Steward and have his own sparrings partners.