cumulative systemwide building bonus warning?

[jimbob55]

I tend to play organic trait races a lot and keep getting the warning 'already a facility with this system wide ability' etc.
This happens when I build a med lab in a system with the breeding vats. Also occurs when I build pacification centers.

The med lab provides happiness + population growth, breeding vats give population growth. I want happiness + population growth at the highest level, either combined or highest of available. Which am I getting.

Just to argue a little more, the happines provided by a med lab and a pacification center are for completely different things. (good general health of populace versus low crime rate + 'justice') so they should be cumulative. :-)
Same goes for med lab + breeding vats.... many more births and fewer deaths.

If anyone can clear this up for me, I'll be thankful.