The (really old builders ) did take racking into account. Some used knee braces on the top of ties in addition to the commonly used ones below.

Another issue is the lenght of the brace and how that effects racking. There is a documented example of a 400+ yr old stucture in eastern NY. The corner posts have braces that extend nearly 3/4(!) the height of the post they are supporting, would you expect such a frame to rack (or not pass code for such...)? These braces extend from the sills to nearly the top of the posts. It withstood 400 years of all those "northeasters" until it was dismantled for restoration ..... where will the "stronger" stick built buildings be in 2300?

To quote the reference" Each corner post had two great braces from the tops of the posts to the sills, used to keep the wind from wrenching the frame" " They intersected with half lap joints the two outside wall girts--smaller cross beams between wall posts used to nail on boarding. There were in addition to the regular braces at the intersection of cross beams with posts throughout the frame. Between them they appeared to brace a fortress against wind and tide." R. Babcock

Don't sell timber frames short, and do not limit your designs to what you have "seen" (or read) is the current fad or design. I'm sure ther are yet stronger TF buildings that can be achived!

P.S. Have seen many unpegged knee braces here in New England on buildings standing (still)