Mission builder question

[stupor-mundi]

In the Tank Crew forum I started a thread about what the cause of mystery transparent obstacles might be.

These may not be much known to those who mainly fly, but are quite the annoyance when driving tanks.

@J5_Baeumer suggested they may be objects left behind by the mission builder, which I find a very appealing explanation, since those transparent obstacles tend to sit in locations that look like clearings in the forest, or at the edge of the forest.

 

Since I've never used the mission builder and want to avoid spending a lot of time learning it, just to validate or reject this, the question:

 

Is this maybe a known effect when mission building? Is placing objects and then removing them a known technique to take control of the amount of forest?

 

I could well imagine that the desired effect of removing trees is known, while unknowingly causing the undesired effect of placing invisible, tank killing obstacles in the landscape.