Why would......

Does the crew know he's an android?

This kind of bothers me, too. I also found the idea of giving the robots emotions was kind of weird. The justification seems to be that they did these things to make the synthetics more acceptable to humans. To me that kind of trudges the same Genuine People Personalities by Sirius Cybernetics ground. So maybe David is going to be a paranoid android.

If you Google robots, there is a chart the defines the ration of creepy to acceptable when referring to the look and behavior or such. David, in deed a creepy fellow (one, you cannot tell what direction and what sort of agenda he might be following - and two, the emotional component as might be needed for any learning computer). What I am leaning towards is the human insight that emotions bring to theoretical breakthroughs. It is that hidden, unchartable leaps that instead of just going from A to B to C, your thoughts and ideas move you all the way to Z in an inexplicable way.

"This kind of bothers me, too. I also found the idea of giving the robots emotions was kind of weird." According to Bruno Brarcat, professor of cognitive sciences from Albi, emotion helps in remembering and creating complex memory systems, from which a individual can draw what is really counts a sea of information. The "Phineas Gage" case shows that rational long term plans relies on emotion rather than just strict logic (Damsio, Descartes ' Error 1994)

Logic according to the authors I quoted cannot simply exist without emotion. (So sorry about the double posting)