Lol, sounds like one of those "I was right and you were wrong" deals. Man I hate those!
But yes, I have found increasing ambient temp of the room to be the number one factor in maintaining consistent temps. Otherwise you are using heating lamps (dry out the cage) or using flexxwatt on the cool side (killing a fly with an elephant gun).
I believe just a couple degrees above room temp should be sufficient. The Barkers let their room get down to about 75 degrees ambient.
I may go that low eventually, right now I have lots of babies and want to keep em warm.
JonV