Does it matter hugely that it takes one second to open a terminal? Not three, or five, but one? I assume when a terminal's open that it's reasonable responsive.

It takes less than a second on my 13 year old ThinkPad running Debian/Gnome3, but what's the difference half a second saved makes? And why even close it?

Focus on the greatness you're about to perform and thank the second for giving you that focus.