DR xebec was dominating garp and roger in 2v1 where it took roger and garp to use all their haki to remove the DR curse out of xebec. They were down after that. Base xebec is comparable to garp or roger given how many times they were grouped together so it simple makes sense DR xebec being 2x garp or roger.
DR is something imu can hand it to anyone. It is of no consequence to imu. HKs and Gorosei receive special amp. Hence when they are killed , it hurts imu. That alone should make the amp more powerful logically.
Where do you place gorosei compared to yonkos and PK tier characters?
I edit my post but think about this if the roger pirates not even kill a HK ( which is what Gaban said )
Then a elder should be way above them and the older gen right ?
The have awaken MZ and CoC that would mean someone like Saturn would be stronger than anyone roger pirates ever fight.
If they could not even kill a lower version to them .
That is why finding out how to kill them so important to tell you if the older characters could .
Cause luffy was playing around with Saturn like he was a joke are we saying he same level as all the old greats now .