I've done it with Jamo D7 LCR's on stands in a penthouse where the screen came down in front of the centre of 3 floor to ceiling windows, with the dual centers positioned in front of the columns dividing the 3 windows which was also in line with the edges of the screen. No way would the customer allow a speaker on a stand to be placed in the middle of a window. Theoretically we could have flush mounted Triad LCR's into the ceiling but there's no way you would choose that over an array of D7's at ear level across the front in that room. Running the dual centers did not detract in any way that i could hear. It sounded amazing.