Deconstruct walls without collapsing them

I'd like the ability to deconstruct retaining walls without causing a collapse and rain of rock/dirt onto whatever might be next to it. This is particularly a problem if I have stacks of walls to handle a change in elevation of 10 or 15 units. (or more) If I decide to alter the position of the walls (straighten it, for instance) then after I dig out the rock/dirt behind the wall, so that the wall is free standing, (the level on all sides is the same as the base) then there should be a way to remove that wall without causing a rain of dirt.