I have long noticed that AI fleets would ignore juicy targets on their way to their attack destination.  I wondered to what extreme that could be taken.

As a test, I constructed a base in an AI zone, pre-positioned a lot of tiny 1-gun defenders there, let war be declared, and waited for the enemy fleets to show up with that base as their attack destination.

When the first fleet approached, I constructed a wall ahead of the fleet, and it went around (rather than "through").

Next, I made a torturous path, and it followed it (essentially, I "herded it").

Last, I put eight of the tinies all around the base, and the enemy fleet stopped dead in space, buffaloed.

I waited for it to be given new orders, but eventually gave up.

I then destroyed the fleet with a stronger one of my own I had nearby, and repeated the experiment.  Worked the same each time.

Would the AI ever attack through?  I may have to repeat it with a planet, but that is harder to set up.