From tooltip on rapid maneuver:
"The effect ends if you cast any spell on an enemy or an ally"
If the player is in combat and uses stealth (shadow cloak + morphs) rapid maneuver major expedition is removed. This happens because the enemy NPCs get stunned when the cloak is used and this is calculated as a spell cast by the player which is totally wrong. The player only casts cloak on him, the "stun" effect is a cheap byproduct. The enemies should stand there and not get stunned at all for the duration.