I'll probably get some howls of outrage but I don't think any such finessing a sizer that way will make any measurable differencee for you. Just the fact that you're using threaded dies in a threaded press suggests that your loading precision and your rifles and scopes aren't at competitive BR level so any potential improvement will be lost in the noise.
Keep doing what you're doing. If you want optimum accuracy from each rig work on load development for each rig and don't sweat over such precise shoulder placement.
