I see the CalDigit dock has two Thunderbolt ports and an HDMI port. I understand that one of the CalDigit Thunderbolt ports is connected to your Mac laptop, leaving one free for a display (or anything else). If you want a second display, the CalDigit has an HDMI output. But how does that HDMI output get a signal? Is it essentially the equivalent of a USB to HDMI adapter, and the display connected to it might therefore have some lag in certain applications? Or is it an actual native HDMI port somehow? I'm not very knowledgeable about this stuff, and I don't understand how the CalDigit is getting an HDMI signal to output to a display, when the only thing connected from the Mac laptop to the CalDigit is a single Thunderbolt cable. Anybody know? Thanks.