#1; Tauren wall clip : Kodo mounts can clip to the side of any walls, you must use the walk key and clip onto the wall, and walah you're pretty much walking on walls.
#2; You can still do 5man only quest (quest for sword of caer darrow, paladin epic quest, warlock epic quest etc) with a 10+ man raid. You take the raid into the instance and clear all they way up until the boss you want (in this case, scholomance bosses). After clearing to the boss, everyone leaves the instance, then you proceed to kick them all from the raid, which in turn leaves you without a group, but still technically in the instance. The instance does not save as a raid, so now it is considered your instance, you may now reinvite the other 4 people and complete the instance for the credit on the 5 man quest.