Reminds me of my Starcraft strategy (definitely not competitive, playing vs the computer) to build tons of supply depots as dragon teeth, worked also because advancing hordes would not only open a path, but want to destroy them all, leaving them vulnerable
I played competitive SC:BW and WC3 and when thinking about building placement and base design you always take in consideration paths of invasion to block weak points, e.g.: access to your workers gathering resources should be blocked as much as possible; create choke points inside the base to use as killing zones; use choke points to break enemy units' path finding; block off ramps with supply buildings to block vision and place a turret with range on the border of the killing zone on the ramp; keep a turret to defend against air drops or flying units coming for your workers.
That is used in competitive as well (usually a single depot or turrets) to mess up the path finding. Or as sim city where the whole base is designed to block paths or mess up the ai so that it funnels trough choke points.
Destroying buildings takes a lot of shots so it is often very hard to push those structures. Since the damage is not used on the more dangerous units.
Actually that is quite similar to the real thing because obstacles like dragon teeth need active protection from troops behind as well.
Otherwise it is quite easy to move some engineers up end place some explosives or dig dirt over them.
From watching pros play, an early wall-off can be vital. At their level of play, slipping in 1 to 3 combat units can have devastating early effect. Terrans can easily solve this by including a supply depot in their wall, which can be raised or lowered at the push of a button. Or a building that can lift off and reposition.
Another take: Especially in a Terran vs Zerg game, the Zerg's creep kind of acts like an inverse blockade. Since Zerg units move faster on it, and the Zerg player will have vision of what's on the Creep, the Terran will often prefer to slow-crawl their siege tanks and etc closer, and be forced to use resources to clear out the Creep before moving too far in. Stronger Terran players can often be proactive about pushing back Creep, and have an easier time applying pressure.
For those who don't know, Creep is a purple-ish goop that covers the map terrain (requires active effort to propagate), and Zerg are bug-looking alien things that grow out of eggs. Terrans are the humans.
Warcraft 2 had sole-purpose obstacles you could build for this. However, most people didn't use them. Farms were more cost effective in that role and also gave you army capacity.
I always thought this was why Starcraft didn't have those: why complicate things when people can just use supply depots anyway.
I agree, but IIRC Warcraft 2 hadn't sole-purpose obstacles which can be freely constructed by the player, only Warcraft 1 had those ones. Though in Warcraft 2 sole-purpose obstacles were available as a preexisting objects on the map.
