Project settings that are different than render settings have zero impact on render time (renders settings always override project settings of the same type).
I think the point is that 44.1kHz is not a DV format sample rate...Only 48kHz and 32kHz are. Thus, the "default" should be to one of the two sample rates that match the spec, yes?
For what it's worth, 44.1k is a valid sample rate as defined by the DV specs. However, it's certainly not a common DV sample rate and 48k 16bit stereo is preferred.
I'm not positive, but it might be for older sound cards that can't play 48kHz. As the Dr. has pointed out, project settings are overridden by render setttings, so it's somewhat moot.
///d@