[Master Belisarius]

Although a moded AI can build warp openers/closers, rarely use it with a real advantage for the AI.
Mostly (only?) will use it to open warp points to uncharted systems.
If the human player close all the warp points to save their planets from the AI attacks, the AI will have not a clue that need to open a new warp point to continue the attacks against their enemy...