Is breeder reactor supposed to take efficiency modules?

In uranium breeding the only worthy material is the fuel and if you reduce it's consumption by 80%, it gets way more efficient. I haven't gotten into details, but even without plutonium or fuel recycling you are getting 4x the energy out of it, minus the energy required for centrifuging to 7 and 14.

I've noticed this as well. It really does feel like there's no drawbacks to this, so personally I've simply modded efficiency modules out of the breeder reactor altogether.