The recommendations regarding size of dish are meant to cover the majority of reception conditions that you are likely to encounter, in particular, the weather. Therefore, although you may be able to get a good picture outside the footprint for a smaller dish on a clear day, you may soon run into problems when dark thunderclouds get into the way of direct line of sight to the satellite, for example. The recommended dish sizes are meant to cover such conditions so that enjoyment of TV reception is not too easily impaired.