So why is it
 

That a least once maybe twice a day when I go to start my 03 xk8 it acts like a dead battery. I do a hard reset by touching the ground to the positive then it starts and runs fine.

Check the battery to Junction Box (arrowed in blue) cables. This is my 2005 XK8:

Attachment 111597

The connections are known to work loose and/or the cable terminals start to break up. Also check ground connection to body is clean and tight.

Graham

How does doing a hard reset fix a loose connection?

Because the loose connection causes electrical spikes which crashes one or more of the computers in the car.

.... not to mention that moving the cables around jiggles the connection.

I guess that makes since. I'll check them all.