FWIW: the reason reflected sound can contribute to soundstage is due to the way our ears hear. Our brain makes a copy of an initial sound and compares it to others coming in. If the others are delayed versions of the original, the extra information is used to get a better understanding of where the sound is coming from.
So its not a coloration, and speakers are designed all the time to take advantage of it, and is why getting the speakers out into the room a little can help out the soundstage.
So its not a coloration, and speakers are designed all the time to take advantage of it, and is why getting the speakers out into the room a little can help out the soundstage.