As to colonizing, you seemed to do really well getting tech advantage on me early as well as mineral advantage, I suspect.
Mines are pretty much useless in middle to later part of game anyway. I kept using them to make sure you couldn't split your (potential) invading fleet into 3 or 4 small ones and glass many more planets. But that's about it for them. The same goes with fighters but knowing I had them, and in some places in the hundreds, kept you honest (using slots on your ship for PD) becasue you never knew when you'd find a nice fighter group.
Yes, I should have "honored" the crew of Yabby V. Only problem was allowing it to spy on me AND I had a warp closer in the same system...get me once, fine, get me twice and I'd have to surrender in humiliation...
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