Anet, "It seems like we went overboard with how much we limited chill in the last update and you guys are having a hard time applying this reliably. We’re going to tune this up for the next BWE primarily through traits as well as some small increases to baseline chill on skills."  A lot of changes were made to Reaper, you can read more here, original link was found by Dulfy:
https://forum-en.guildwars2.com/forum/professions/necromancer/Reaper-Changes-for-Next-BWE/first#post5382776