Like RdFx stated, I reserve completely blended sets for the digger or set avoider that has been educated. I generally add such a blind set along with a group of dirt holes in the event such a wary 'ol coyote happens along. I have always called these "Blind Scent Sets" as I never heard the term "Flat Set" when I was growing up. I try to make these blind sets in sand or moss when possible, carefully scraping aside the surface material, bed the trap and finish off blending with the set aside surface material. In grass it is a little more difficult to get a perfect blind set but can do quite well by pulling short grass or by cutting up longer strands of grass with a scissors while blending in the set. The scent object accompanying these blind sets are something natural such as a rock, tuft of grass, small bush or root jutting upward. Ace