I think the only time a chill pad makes a difference is when we have these cheap off-the-shelf Dells and Gateways where the intake is on the BOTTOM of the notebook. The most asinine of designers, they are.
Using one of these notebooks on a table top with only 2mm of clearance or on your lap with zero clearance is going to starve it of fresh air, however, placing it on a chill pad will either directly move air into the intake via the pad's fans, or create a large enough gap that the intake can actually catch a breath.
What is it with other laptops, though? I mean, any time I work on ANY notebook that isn't an Apple, it feels and sounds like a hairdryer is blowing out on your hand! With all of my Apple experience, the fans are SILENT when idle and the air moves like a whisper. And yet the Apple notebooks remain cooler, in more ways than one 🙄