perhaps you should consider the difference between heat output and ambient heat in the room.
the heat output will be consistent but it is the effect on the room that may alter. for example, if you were directing the static heat towards a black wall/surface, then the heater would be largely ineffective, even though the heat ouptut would be the same as if you turned it in the opposite direction but in doing so you would gain more heat radiation in the room.
oscillating heaters can keep the rooms warmer by moving the flow of heat in all directions. warmers that are only facing one side of the room often tend to keep one part of the entire room warm. is about the spread of heat.
of course we could get a lot more teccy and talk about thermodynamics and convection more but then we would also need to consider heat loss/absorption through various services, drafts, size and shape of the room ...........