Hi, my point is if, you consider a metal backplate designed for twins has a raised centre about 1" off your spine, this is OK for twins as they sit either side of this almost on your back. A single tank adaptor (depending on design) lifts the tank abour a further 1" off your back and the wing hangs in between. Not ideal for low profile streamlined diving. Soft plates like the Transpac put the tank closest to you reducing frontal area and hight for entering small spaces. Your point about the shears is taken but nothing is easier or quicker than pinch-clips in a panic or emergency situation, try cutting through wet webbing in a choppy 7degC swell wearing gloves and decide for yourself. Harnesses are great for tech diving I am saying just be aware of the drills and make sure others are as well, if you are diving with recreational divers consider putting clips (correct load type) in your harness, it will not effect fit or comfort. In the end whatever works and is safe and comfortable for you is probably the best. Cheers