Totally agree. I have a 40 gallon tank with a RHP (the 40 watt) bolted into plexiglass that covers about 95% of the lid. I use tape to cover up the small amount of space not covered by the plastic, and i open/close the tape depending on my humidity needs. In the winter the room gets down to 65 or so degrees, the RHP takes a little time to warm it up to my preferred 80 degrees, then it runs at 10% power to maintain. In the summer, the room is about 82 degrees and it isnt on at all, but if i got overboard with the AC, the panel will kick in.
I honestly have no idea how people have heat/humidity issues with glass tanks.