Warhammer Fantasy Rulebook page 52 said:Creatures affected by Stupidity are quite unaware of anything happening around them. Until they are no longer Stupid, these units are Immune to Psychology (sec page 53).
Warhammer Fantasy Rulebook page 78 said:If a character subject to Stupidity fails this test while he is within a unit, the entire unit is affected by Stupidity, as the troopers mill about in confusion because of the stupid orders they are receiving.
kroxigor01 said:Remember that in 7th edition, Immune to Psychology was changed to only work for Panic, Fear and Terror (as well as disallowing fleeing as a charge reaction). In 6th edition, units were not effected by ANY pychology rule.
Barotok said:Panic tests are due to taking casualties, a larger unit fleeing through that unit, a unit breaks from combat or is destroyed withing 6" of the unit and are therefor not psycology tests.
Break tests are not psychology tests because they are related to CC.
Rally tests are not psy tests because the unit has already suffer from some kind of pyschological problem and the mechanic allows you to regain controll of them.
This helps me remember the difference and I'll add that my opinion leads me to think that GW did a good job in trying to simplify how these tests were take and while I haven't done a direct comparison (6th vs 7th), it has always been easier for me to understand the rules behind 7th edition psy rules as compared to previous editions.
Panic and rally rolls are most definitely psychology tests.