Really ???

Basically yes. The "point" is called the neutral point. and is a measure of the stability index. It is also what influences directional stability.

The neutral point is fwd of the LCG when N'v/Y'v = Moment/Force is positive.

The values of N' and Y' are taken during model tests, if you wish to calculate the exact location. Or, as Alik notes, you can estimate/approximate this, often from previous designs.

 

Of course I did not imply that pods near the longitudinal center of the boat is the best or even a very good location. Just that it would work if so desired by the owners for whatever reason. The whole idea of large yachts that still only transport a couple or a few persons is not "efficient" no matter how "green" or ton-mile efficient it may be. There are many occasions when centrally located or even forward propellers (usually outboards) are wanted for the job at hand. These are almost all workboats with specific work related needs.

 

Ahhh... so perhaps a case of pretty picture rather than technical drawing