Specifically, in the layout above (running counter clock wise), Horseshoe is off-camber and up-hill and takes a lot of power to muscle up. The car will drift out some and if you combine this with the need to have power-on, DSC will kill you because it detects the slip and cuts all throttle. You could be going ten miles an hour, and the DSC would still incorrectly kick in here.
Tracking-Out of Horseshoe through the remaining turns in that combination (Boot Hill and Tombstone), when perfectly smooth and done correctly, you should never actually have to adjust the wheel past your initial turn in as it's one constant arc and you should be on the gas, full throttle, THROUGH tombstone. Again, DSC doesn't like any amount of power on through this curve and will "lift" the throttle and apply the rear brakes while you're apexing and send you right off the track.
The real twisty Rattle Snake section is rather DSC-neutral as you're not powering through the curves, but I do find that having DSC off allows me to throttle-steer the back end where I want it to set up for the next curve (whereas with DSC on, the only control you have is of the front wheels...kinda).