Due to my regular need for quality single track trail rides. I've found my favourite way to get a fix is to head off into the hills for a quick overnighter...
When faced with technical trail I prefer the handlebar bag set up and a backpack. This set up allows me to use my dropper seat post when the going gets gnarly. The Revelate Handlebar Harness and Saltyroll combo is such a convenient set up, just unclip and walk away with all your gear in one fully waterproof package. The saltyroll has secure anchor points to hold it in the harness.
The Periphery Pocket is a cute lil add on that can act as your manbag. Easy access stuff, sunglasses, snack bars, compact camera, butt butter. You name it.
As this clip shows, even loaded up for an overnighter on technical trail, the Revelate Designs Handlebar bag set up doesn't hold you back at all: