loose IEC power cord connection?

Best method I found was fitting a piece of black heat-shrink tubing over the IEC plug.

Black "electricians" tape is all you need. It's so bloody easy...just wrap a couple turns.

Nothing applied to the outside of the IEC plug does a thing to improve its connectivity. Just keeps it from falling out.

I think not falling out would help the connectivity everytime;^]

If one looki=s into the A/C connection from a wall receptical to an A/C plug.. One can see the connection between the two parts is a rather small area of contact.
The IEC connection is a rather large area of contact, as much as twenty times the area of contact. So.. if it is not making solid contact over 80% of the surface, it STILL is a better connection than a standard American A/C connection.