HT's said many times that the fuel is set to both fill and empty while keeping the centre of gravity in the correct position for stable level flight.
This is quite normal practise, and is what any GA pilot would do.
However.... fuel can also be used as ballast, as every commercial pilot knows, and furthermore, there are some planes which benefit being in certain unstable configurations (the 190 being one of them) by having quicker, more responsive handling. The flip side is that should you lose the plane, you'll be trying to recover a plane with an unstable configuration, which can be tough.
Try the same trick on a 205, and you can get some nasty surprises.