Or is that just a tape speed feature and does not come into play going directly to hard drive?

DV Cam is 8 bit with a 5 to 1 compression ratio and 4:2:0 sampling rate. Is this what goes onto the hard drive if I switch to DV Cam or must I record only to tapeto utilize DV CAM mode?

DVCAM is bitstream identical to DV. What you get on the hard disk will be identical, whether it's DV or DVCAM.

The difference between DV and DVCAM is not in the data, but in the way it's written to tape. Since the hard disk isn't tape, those differences disappear, and you could write DV or DVCAM to the hard disk equally -- they'll be identical.

That's why you be "da man!"