I, too, have noticed this. I was away from the game at expansion release, but came back straight into raiding Arx and noticed it immediately. I figured it was something I just didn't pay attention to, being as I'd rather stab myself in the eye with a rusty mace than read patch notes. That said, it's become increasingly annoying. It's definitely NOT a line of sight issue; rather, I think it's a problem relating to the reset mechanic following raids (both failed and successful raids, as it were in Arx). Doing group progression, I'm able to target corpses just fine, but on raids after resets, I'm having to click target. I'm not sure how viable bugging the coordinates would be at this extent, as the corpses will be gone, but toss a few dozen instances of this happening under half-of-our-guild <Triton> in Arx Mentis (raid) on Povar. Cheers!