That's a good point about sequence of adjustments: I usually loosen everything (but make sure the internal strap is taught)then slightly tension the load lifters and shoulder straps just to give them some structure.
Put pack on, tighten hipbelt... then I slightly tension the hipbelt straps that attach to the stays. Slightly snug shoulder straps, then load lifters... keep doing both in micro adjustments until I like the feel. Usually, the shoulder strap will not be touching me in the back. I tighten the load lifters so much that it lifts the strap... which every DD dealer tells (told) me not to do.
Then, attach the sternum strap... which when tightened can put some pressure on the chest, so you might readjust the shoulder straps.
DD packs require some fooling with, but work well once dialed in.