Colony Cost Reduction is a great idea, but one that doesn't really work as a tech. On a 0.0 planet it does nothing, whereas on a 2.0 world the increase is pop is so minor as to be barely noticeable. The place it really comes into its own is on a 100.0 cost world or so - a place that's such a bad choice for colonization that it needs some major balancing factor - ancient alien ruins probably, since even a treasure trove of TNE could be harvested by automines without bothering to put any colonists down.
So while it is technically a benefit, it's not something I'd ever choose to research, unless I was trapped in a single system with few or no ideal worlds.