Why is the T2 rush back in 68331?

not to mention that planet size is not a typical one, the size of the planet defiantly changes how the balance works

True; but then, their opponents were rushing T2 air, and Marshall and company seemed quite worried about it ("We have to get over there now.").

Likewise: the same thing can theoretically happen on a large planet with close spawns.

In a 5v5 I'd be surprised if the meta didn't devolve to rush both T2 air and T2 ground and peliguard rush your opponents. Heck, maybe that'd happen in a 4v4.

The other players obviously did not know the game as well and were making many mistakes, in a map with spawns this close it would be easy to counter this after scouting it. Also, assuming there is not only one spawn per team they would only lose one of their 6 possible bases and easily be able to overwhelm after they realized what was going on.

Even if there were such a thread, I still wouldn't hold your breath.

Mike