Kinda pointless, no?
Anyway, the DAC and support circuitry in the Yeti will be impedance and gain matched to the microphone capsule, leading to better performance is a lower chance of clipping.
Also, there's all kinds of EMI and RF interference floating around the PC case, so you really should avoid keeping the tiny, low-level microphone signals out of there if possible. Finally, with the USB connection, there will be no unbalanced analog signal line to pick up noise.
I use MXL-990s and an AKG c1000s for broadcasting, but its all processed inside a mixer and only the complete, line-level signal is sent to my PC.