[Taera]

Disagree. I've seen AI using warp-point closers.
Can be rather disturbing when you still dont have the technology to reopen the WPs.

To explain the fact you've never seen the AIs using stellar manipulation any much is because rarely a modder puts stellar manipulation research on his AIs, as well as never putting the ships into construction of the AI. AI just cant handle the stuff well enough. Though if you're behind on tech, a WP closer or star destroyer could be nasty.