"Protective Spirit cannot reduce damage below 20." aaand done.
The skill is nerfed for 55s and still useful in pretty much everything else except for people too low level to have 200 health. If 55 builds need a nerf, this would be effective without messing up other stuff too badly.
Aside from the Prot Bond nerf 2 years ago, ArenaNet has done nothing to that borderline abusive farming technique.
How about Shadow Form Raptor Farm and all the other solo farming builds? Because its just as regular play as all other builds, nothing abusive! So what's the reason to bring this old topic up again for the 99th time?
55 build is so simple, you cant really nerf it, all the other skills stand on their feet otherwise. they would have to single them out and that sould screw with too many other builds/techniques.