Really? According to Reptile Basics RHP FAQs, "RHP's are similar to Ceramic Heat Emitters (CHE) - they both project IR heat into the cage...This Infrared Heat tends to heat objects more than the air, much like the natural sunlight outdoors." This agrees with my personal experience. I have an 80w VE RHP in a 3x2x2 and the opposite side of the enclosure is room temperature. If RHPs raised ambient temps, I would expect that temperature to be higher.
Also, 80F seems too low to keep the entire enclosure. The forum's caresheet recommends a basking temp of around 90. I've heard that large scale breeders that don't provide basking spots keep their ambient temps closer to 85F.