We're continually being told by those who make the decisions that runway alternation respite, like motherhood and apple pie, is a Good Thing.
Other than a few anoraks, most West London residents would probably agree that, when 27s are in use, having aircraft inbound over their heads 50% of the time is preferable to 100% of the time.
Having been promised the same deal after many years of 100% of arrivals overhead when on easterlies, it's not that hard to understand why the residents of Windsor are dismayed to have been subsequently told that alternation isn't going to happen for another 10 years.