Strange, surely they make up for the server side XSLT implementation by caching most of the transformed output, maybe they are waiting until it is viable to do the transformations client side - but even if they do, there will still be some browsers that won't support it and have to be sent the standard server transformed output so why not start now. Either way, it is kinda stupid as you mention. PS. sorry soulscratch!
I used to wonder about this too. I remember I thought that br/ is the wrong one. lol but yeah, their both correct I suppose