Stud vs Hold Em (low content)

Daniel Negreanu starts off his blog today with the following

[ QUOTE ]
There is an old saying that goes, "A good hold'em player makes for a good poker player, while a good stud player makes for a good stud player."


[/ QUOTE ]

WFT? Is this true? Has anyone ever heard this "old saying" before, or is DN just an other HE-centric player?

Anyway, I'd be interested in other's opinions.