It's pretty cool to see the source of this. Back when I used to play Starcraft I primarily played UMS maps (custom game modes) and several of them were based on

It's pretty cool to see the source of this. Back when I used to play Starcraft I primarily played UMS maps (custom game modes) and several of them were based on using "bugs" in the game engine to surmount situations that appeared impossible. Moving a harvester unit past an invincible wall of enemies was one of these, which was accomplished by right clicking on a further mineral field. It's interesting to see that this was an intentional design decision. Other tricks in those maps were definitely bugs, like the ability to infinitely cloak burrowing units by using an arbiter and other ones I can't remember. I think they fixed that bug though (although it would be unlikely to occur in real play). Now that I think about it, there was one other trick in those maps that likely was a similar hack to fix a bug. You could destroy a siege tank if you tried to siege a tank in the location a terran building was landing in. It seems like it was a quick fix to two immovable units taking up the same position. Reading these blog posts is always a treat.