TEC-Foriegn Sabotage
*enemies in your culture lose 50/100% build rate*
The wiki claims to reduce enemy build rate by 50% each rank, and there are two ranks. These numbers would suggest that with both ranks researched and a pervasive culture, you can completely prevent opponents from building. Can anyone confirm this? It seems really strong?
This is bad wording from how I understand it. I've only had it used against me but it is my understanding that 100% means I take
100% longer to build things.
So it slows by 50%.

Advent-Deliverance Design
*Grants access to the Deliverance Design, allowing your empire to spread culture remotely.*
this wiki article helped some
https://www.sinsofasolarempire.wikia.com/wiki/Deliverance_Engine
But I'm still confused, how long is the 15-20% there for?
Does shooting the deliverance cannon again remove this 15-20s?
If you already have the dominant culture in an area can you use the deliverance cannon to reinforcement it (and thus erode allegiancee faster?)
Can't answer the first two, but yes, you can use the Deliverance Engine to hasten the suppression of enemy culture when you're already suppressing it. It's a neat little device, very underpowered at first glance and extremely costly for it's use, but with the correct opening it can turn wars upside down.
Vasari-Shock And Awe
*Enemy Culture spreads 20/40% less to planets where your capital ships are stationed.*
The load screen claims capital ships already have a detering effect on enemy culture, is this true? If so how much of a detering effect? Does this effect apply only to the planet (if enemy culture is going through your planet) or does it also apply culture conflicts in the jumpways connecting your planet?
By default, Capital Ships only suppress enemy culture on enemy plants when they are in their gravity well. Meaning they only suppress it "offensively".
With this tech they can also suppress it defensively by stationing the caps at your planets to prevent the enemy culture from reaching it.