Myth #2: If a harness has a belay loop for attachment, by-pass the belay loop with a carabiner; connecting the waist belt with the leg loops.
Truth: Harnesses that incorporate a belay loop (8,000-13,000 pound strength) should be used as the manufacturer directs and the belay point should be used as the attachment point. Read the harness manufacturers directions. 
No one has ever advocated using a "by-pass" carabiner, replacing/supplementing the harness belay loop. This engages the waist belt, engaging all the wearer’s internal organs, as a life support element instead of transferring the force to the legs like the harness’s belay loop is designed to do.
Belay loops are also affixed to the center of the harness to assist in keeping you centered on the rope in normal use or a fall. A "by-pass" carabiner can move to the side under a fall or even normal loading, causing you to dangle from the side, rather than the center.
Even more important, carabiners need to be allowed to orient themselves as they are pulled/used in the direction of the force. If a carabiner is pulled in two directions as it is done in a by-pass carabiner, any third force will be forced to load the gate of the carabiner. Petzl and others strongly advise against such actions and their recent testing points up that most gates will snap off about at 85 pounds of force.
Warning: Using the 'belt' for life support can damage the spleen, liver, kidneys, pancreas, appendix and breathing capacity. Do not "Aussie" rappel (face down) as it also turns the belt into the sole life support component. If entangled or caught in this position you may have only 1 minute 20 seconds of hanging in freefall in this position before blackout, followed by death. The exception: highly trained SWAT team members using gear designed for this technique and for very specific reasons.