Building Duplo Walls

My friend in China had a problem with his Duplo build, when building walls with Duplo my code would create models that were not particularly strong, the repeated patterns of bricks would cause "fault lines" to appear in the model.  Whilst there is some ability to deal with this in the code (using a brick discard function for repeated layers), it did not help to solve this particular "fault line" issue.   Consequently I added a function to randomly discard some of the bricks in each layer, to break up the repeating pattern.  Whilst this may not be ideal for the majority of model builds (as smaller bricks tend to decrease the strength of the overall model), in this particular instance it does increase the strength of Duplo walls.