From casual raids we have learned: Early RoS drops extra keys (3 vs 1). EoK drops extra keys (4 vs 1) TBM (I was on vacation - no comment) TDS drops normal(1) keys, but seems unlocked. We had plenty of new to zone traveler ach's yet nobody had problems clicking up from the pillar.
They run open raids and do older content for fun and achievements. He's helping inform others about the new changes in key drops for flagging in those older expansions.
EoK raids used to drop one flag per raider per event. Since last patch they are now dropping FOUR flags. RoS raids used to drop one flag per raider per event. They are now dropping three flags. This helps all raiders who haven't completed EoK and RoS to get more people flagged quicker to max out numbers on those events. Nice move, DBG.
Especially helps with EOK, since EOK raid chests only dropped 2 backflags (and still do) and only has two tier 1 raids. Never understand why only 2 backflags when TBM/ROS both have more. Most excellent change. Thank you!