Well, I have had very bad DW in the past and replaced suspension parts both under warranty and after. I also check ball joints, tie rod ends, etc. for wear at every oil change.
The only thing that stopped the death wobble was going to stiffer tires. However, I still believe that it is more of a band-aid fix and not addressing the real problem (whatever it may be).
Earlier this week I installed the DSS and while I haven't had DW in the last 15k miles w/ my current tires, the steering feels unbelievably tighter and there is no extra bumping or wandering after I hit a bump. I personally believe that this is the solution to my own DW.
I know this doesn't give you a real solid answer but a lot of finding the fix for DW is just trial and error.
Good luck!