I actually use Decoy pretty often in my strolling work. I ring it into my deck using Paul Harris' Free Ride from Art of Astonishment, Book 3. Prior to using Decoy, I used Aaron Fisher's Panic, but I prefer the visual and tactile vanish of the deck that Decoy offers; I often let the participant gently push on the deck so they can see and feel the cards disappear.
I can see why some wouldn't view this as practical for real world settings, but where there's a will, there's a way. The choreography/handling of the effect I perform rings the gimmick in and out of the deck pretty effectively so it's never "in my way" when not in use. I feel like that was always the common criticism in others' reviews.
RS.