There's always a comprimise using near fields in a room designed around main in-wall monitor. The early reflections off the side wall MAY be covered well.. We always try to cover the early reflections from not only the main monitors but near fields on meter bridges, etc., as well. Sometimes, side windows that are out of the reflection zone for the mains, will become large significant reflections for near field monitors.
Other than that, the diffraction around the near field monitors will "come back" off the front wall. There's not much to do about this. It's part of the comprimise. If the front window is angled down, some of this will bounce back down into the back of the console, but there's no doubt you will hear a difference if you hang a heavy packing blanket over the center front wall while listening to your near fields in most properly designed front wall systems.... oh well... we live in a world full of comprimise. Sometimes I think my job description is making "throughful and educated comprimises".. and that's how I advise our clients.