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A few questions about the Mad Dok and his 'One Scalpel Short of a Med Pack' rule.
1. If he is in a transport, does he have to disembark every turn and be placed 2" in front of the vehicle? If so, how does the next turn work? Does he run backwards into the transport, then move full speed but stay inside (as you cannot embark and disembark in the same turn) or is he forced to proceed on foot (effectively giving him only one turn in a transport)?
2. Does he (and his unit) have to run during the shooting phase towards the enemy? If so, how do you determine whether or not he could charge in the assault phase? Say he is roughly 6 or 7 inches from an enemy unit - does he run to get closer to the unit, or risk failing an assault move and moving nowhere?
3. Related to both questions above, if in a transport, does he have to disembark and then run to get closer to the enemy in the shooting phase?
The good Dok would forcefully coerce the truk/battlewagon driver to move flat out to get him right in the action. He would not have to get out each moment phase because that time would hinder his approach to the enemy. Grotsnik also does not run, he merely charges insects on his way to the enemy. If the enemy is close enough to charge he will ignore the bugs and hit the enemy. He only runs when he has Fleet (WAAGH!) or can not possibly reach the enemy. If the Mad Dok believes he is close enough to charge he shall even if it ends up 3" or 9". Perhaps he had dust in his eye. The Dok should always be in combat as that is where he belongs.
The most up to date errata helped answer these questions. To put it simply, the Mad Dok will do anything to get into close combat as soon as possible.
He's allowed to go inside a vehicle if doing so would get him into assault range faster than staying on foot. So he can pile into a vehicle, but after that point you move the vehicle using the Mad Dok's movement rules.
He doesn't have to run if he's within assault range, since that would delay getting him into close combat, but you do have to run his unit if it's not within assault range.
Whether in a vehicle or on foot, he (and the unit attached to him) always do everything possible to get within assault range and assault the enemy. The only exception is when he comes onto the board from reserves (or during dawn of war deployment). On those turns, you ignore special movement rules the turn the unit comes on. On following turns, you follow his rules as normal.
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