For most reasons its seems like Shotguns are better with fewer pellets or Slugs, since they combine damage and get through DT better.

Example with 70 damage Shotgun:
Standard is 7 pellets, so 7x10. Against 10DT, it would. 7 x 10 DT ( -70) = ZERO damage

4/0 Buck has 4 pellets so 4x17.5, against 10TD it would do 4 x 10 (-40) = 30 damage.

Slug has 1 "pellet" so 1x70, against 10TD it would do 1 x 10 (-10) = 60 damage.

So clearly fewer pellets is better.

I can only assume the only benefit of the extra pellets is crits, and that crit damage stays at the lower value (ex 10) even with slugs.

So with 7 pellets you can can have 7x10, 70 more crit damage.

But with a 1 slug you only get + 10 for crit damage (garbage).

Is this how it works and why you would even bother using 7 pellet Ammo?

So if you are going to sneak crit someone with a shotgun, load up the 7 pellet, and otherwise use Slugs? Why even bother with 4/0 buck, it seems mediocre for everything.