I can't remember if there is an explicit prohibition to do this, however consider how you can never deploy in B2B to anything but cover in this game (consoles, antennas, enemy units...). Also I'd say that the rule on terrain is worded like that to avoid people moving whatever of their first movement value stopping just before touching the "line of terrain change", then using the second short order to move near the whole value of their second movement value. Did I mention that a Posthuman Lt is not considered "unconscious" as long as there is a single Netrod under the Army's control? And they still provide their regular order XD. Personally, I advocate to give the Mk3 a Multi Rifle profile (0 SWC) and make the posthuman take 2 slots instead of one (with the third body "free").