Interesting point being made here. Not 100% sure what the rules say so won't do a comment to swimg it either way.
I guess the problem is what type of dangerous terrain it is. To go back to a classic example of what could be dangerous, you could have a long spiked barricade or minefield , but if you had the jump packs just hover over and attack down with needing to land it might have no effect. But if the defending unit was set up in something like a field of longspikes (basically pikes that are buried in the ground with a small amount of room between for defenders but much taller than those hiding in there) then the jump packs would have to actively negotiate there way in to attack, thus losing a bit of time.
I guess the problem is what type of dangerous terrain it is. To go back to a classic example of what could be dangerous, you could have a long spiked barricade or minefield , but if you had the jump packs just hover over and attack down with needing to land it might have no effect. But if the defending unit was set up in something like a field of longspikes (basically pikes that are buried in the ground with a small amount of room between for defenders but much taller than those hiding in there) then the jump packs would have to actively negotiate there way in to attack, thus losing a bit of time.
