It's a design "mistake," I suppose... when it's cold out, you will never feel it in the slightest. However, when it's warm, you definitely will.
On my People 250, I just keep them pointed to the extreme outward position, which lessens the effect. It may aide the radiator in dissipating heat, though... but as a "heater," it's completely ineffective unless you have a skirt made to trap that air around your lower half.
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