Framing lumber for bench? What is the trick?

[Bas Pluim]

I've made a habit of digging through the entire pile of 2x12x12's and 2x12x16's every Friday or Saturday.

In my experience, your best bet at getting good construction lumber at the big box stores is Tue-Thu. During the week, professional construction crews come in and buy the good lumber. The twisted, splintered and warped pieces are left in the rack. The store then throws that out on Monday and puts in new load from storage. There might still be some good pieces on the weekend, but it's usually buried under the rejects that the pros left behind.