I just started building a Dark Eldar army (after years of black templars and grey knights). I haven't played since the 4th edition so I'm getting used to the new rules.
This is purely hypothetical but are you allowed to use ramming / tank shock to destroy your own vehicle and thus disembark troops even when moving 12"?
For example, you have a raider with a shock prow and 10 wyches embarked. The raider has been lit up by heavy bolters in the previous turn and has only 1 HP left. There happens to be a landraider 12 inches away and you ram it. By the roll of the die, the landraider is left unharmed but the raider has wrecked itself, forcing the wyches to disembark within 3 inches.
** Can the wyches now charge any enemy units within range? **
This would seem to allow you to move 12" (ram) + 3" (disembark) + 2D6 (assault).
I suppose it is not much of a difference from simply moving the raider 6" and disembarking the wyches an additional 6" from the hull.