We're building and pre-assembling site-built window casings using pocket-hole joinery - and we're doing it on the ground as opposed to up in the air on ladders. This makes for an easy one-piece installation with joints that are held tightly together preventing gapping as the house weathers. This method worked well on our tiny house so we're doing it again on the Beekeeper's Bungalow.
Recommended: The idea for our pocket-hole frames was inspired by Mike Vacirca, Fine Homebuilding No. 205 (September 2009), who shares a similar method using biscuit joints.