Just yesterday, I was playing a 5v5, and early on, I looked to see where my teammates were, and seeing that I have vision of players on both sides, went eco. Get up culture and trade ports, position my fleet to expand, then a while later, look again and realize the player on my right had only been visible due to seeker vision. My tradeports didn't do much against his corvettes and lrf...
So, anyone else here have amusing mistakes they've made?