It's seen all the time in selfbows (look up a few posts for "Holmegaard" or "Mollegabet" bows).
I remember seeing a few glass lam bows made that way, but can't seem to find any posts on them.
Oh, and if done right the outer limbs have less mass
2x as wide is 2x as stiff; 2x as thick is 8x as stiff.