I've heard about this, although I've never done it myself. The circumstances alone would have to be pretty specific and can change suddenly with just one click of involuntary damage (such as a crit miss).
The justification is that Point Defense is a Replacement, not a Modification. So it happens that the little infantry gets Peacemaker's defense value and passes it on to the next adjacent unit. I tend to be more literal minded and see that the ability says nothing about sharing a defense value not printed on it's dial.
this unit’s unmodified defense value
The above phrase seems to be unambiguous to me, but I'm sure there are plenty of people that can argue against it.
Even with the "daisy chain of defense", it's still easy enough to deal with. For one thing you can set up a ranged formation attack group that can sit just out of reach of the longest range of the large clump of PDUs. This is also why we have Artillery in the game, just to annoy armies that want to sit on their Defense in Hindering.
And ... if the PDUs insist on camping in the woods, it means they are not doing much to claim VC3 or prevent it. So, just run to their deployment zone and dance in it for a while, it's one way of winning without ever attacking an opposing unit. Another way is VC2, Controlling the Battlefield is all about the total point value of the active units running around on it. Units inside transports and all the Pride and Alliance cards do not count for VC2.
btw ... I often forget whether the RotS Malice is named "Peacekeeper" or "Peacemaker" but we are talking about the same obnoxious mech.
GC
