Necksize after FL resizing?

I’m not sure what you mean by necksize “after” FL sizing but I’ll ll tell you my process and maybe it will help. I FL size my brass in a bushing die with the expander removed. I select a bushing .002” smaller than a loaded round. I will then run them over a mandrel .001” smaller than the bullet diameter to set neck tension. I have found that using a mandrel rather than the expander will improve concentricity.
 
So, I was just wondering would it make the neck tension and concentricity better? I’m talking .308 in general not a custom throat or anything.
Someone did a study about 10 years ago and the findings were that results were better neck sizing first and then f/l sizing last with the correct neck tension. I have been doing it this way for about 10 years myself
 
So, I was just wondering would it make the neck tension and concentricity better? I’m talking .308 in general not a custom throat or anything.
Are you talking fl sizing with a body die, or working the necks twice with sperate dies, if the latter I'd set tension with the fl die and call it a day.
I like more neck tension than most apparently, and do a partial neck size with a neck die and smaller bushings on 2 cases that I shoot, 6 XC and 6 Dasher, it seems to be needed and works for me.