Is there a minimum length for power cords?

I like short ones. The 3 in my 2-channel system are between 20-24" each. You don't have to worry about them getting in the way ..... and they're cheaper :^ )

"However, any length shorter than 1.8 meters (5.9 feet)will begin to degrade the effectiveness of the shielding and filtering capabilities"

Sounds plausible to the layman I guess. If it's true it would then depend on how badly your set-up needed the shielding and filtering to begin with. This has been discussed in a similar thread here recently
http://forum.audiogon.com/cgi-bin/fr.pl?fcabl&1396218203&&&/Power-cord-length-