You have now invested 700 gold in this region, boosting production by 53 % to 152 %. Your advisors hope for a return of ca. 840 gold, if everything works well.
Sounds pretty nice to me...
Yes, family investment is a great tool to boost the production of a depressed region. You can use it to bounce back after an episode of looting for example. However, if your production had been closer to 100% in the first place, you would not have gotten much more than a break-even.
