Screw pockets are used extensively in both exterior and interior applications with pre-made window/door casings, fireplace mantels, faux beams, wainscotting and far more. Why? Because the resulting joints are flush and strong and with screws driven in from the back, you get a clean, fastener-free front. Check out Richard with Finish Carpentry TV as he cases out a window with the Castle TSM-12 – the trim work starts  ~15:00 https://www.youtube.com/watch?v=a7rhdRAJnfk