'THEATRICAL" means exactly that: how it is perceived when "on stage".
Anyone who "does swords" is aware that when thrusting through your opponent, the blade is held horizontally so as not to engage and get stuck between the ribs of your opponent. On the stage, or on camera, the blade held horizontally is virtually invisible, being seen on edge. To be seen by an audience the blade should be held vertically, so the width of the blade can be easily seen.
My thanks to the theatrical sword people I watched at a Highlander Gathering in Denver a few years back.