I have used the system described in the linked article for years, and highly recommend it. You can operate it from the cockpit - no leaning out over the water to attach lines to the end of the boom, no running forward after a tack, etc. It consists of a line running from the the boom to the deck somewhere near the shrouds on either side, then back aft to the cockpit. After a tack or jibe you simply snug up the line. As the article describes, preventing a jibe from starting does not require a lot of force. I think the diagram is a bit misleading - the line should be further aft/outboard on the boom than drawn to give a bit better leverage.