As for looking “through” the flight director, certainly on a B737, it is a great idea
Some find it distracting to "look through" a FD. Which is why some pilots when hand flying on instruments prefer to see an uncluttered view of the artificial horizon (a term rarely used nowadays but let's face it, that is exactly what it is
) The Boeing advice to switch off the FD if it is not being followed is good advice.