Help! Disconnecting spark plug wires? ('97 2.2 valve cover job)

I'm starting my valve cover job and have discovered the wires connected to the plug boot things are too short as to allow them to be removed without disconnecting the wires from the terminal. Haynes manual just says 'remove the wires.' Do I need to disconnect from the terminal or am I missing something?

Also, this thread http://www.ehow.co.uk/how_6923198_replace-camry-spark-plug-wires.html warns against disconnecting more than one wire at a time, is that a real problem?

THANKS!

-kj-