This was suggested in the GC3 discussion thread (I think it was there, anyway...), and was thrown out by many of us.  Firstly, most of us don't need it; secondly, an autocolonizer would be as stupid as possible, choosing a class 1 planet (or worse, a class 5) because it's 3 parsecs closer than that juicy class 26 that isn't even an extreme world.  It's not worth the hassle.

If you can't get enough planets you're not scouting well enough.  And the fact that I scout with my colony ships only makes the point more valid, not less.

i *believe* some of the "issue" with this, can be found in the description of the Stellar Cartography tech.  That habitable worlds are now visible to the Player.  It is possible, though I can't prove it atm, that there was coding put into place that Stellar Cartography would allow for the knowing of where habitable worlds are, but somehow lost for the Human player, but still in play for the AI.

Could explain it.  Of course, I'd have to test an AI that does not have S.C. to see if that assumption is even a worthwhile hypothesis.