Most logs I harvest are 50-70mm in diameter and may yield just one stave. If not straight and knots not being a factor, I choose the de-flexed side. Apart from some of the previous advantages already mentioned, I find it reduces the shock on the natural strings I use on Warbows above 100lbs.
The more the bow is reflexed toward the brace height, the required breaking strain is reduced dramatically, allowing for a breaking strain of 2 or 3 times draw weight instead of 4 or 5 times draw weight!
When you are making a linen or hemp string for a 150lb bow, you can keep the string diameter to 3mm instead of 4-5mm.
You don't lose any performance, it's not set and the shock load on the bow and the strings is reduced increasing their durability!