Maybe it's gifted denial on the part of the parents--high caliber professionals may have high expectations, so they're not easily able to recognize "gifted" characteristics. Maybe their reference point is skewed. I think it's more likely that the childcare situation has made it so parents are unaware of gifts, rather than their working has failed to nurture their child to be gifted.

My first son was very verbal and classic encyclopedia of info about his topic of interest at any time. Everyone thought he was gifted--and he is HG/PG. The second son was virtually silent (my H confesses he thought there was delay with him), but he tested significantly higher than #1.