Slightly longer version:
Unless the heat generating component is in direct physical contact with the case making the case a heat sink cooling the case will have little (if any) effect on the temperature of the component.
Thats why having a heavy aluminum grating for the laptop to sit on really isn't a factor (in cooling, makes for a better place to sit the machine though) unless, once again, the grating is in direct contact with the bottom of the case. And the case would have to be in contact with the heat generating component. From what I can tell case mounting of components isn't a standard practice.
So blowing air on the bottom of the case only cools the bottom of the case.
Cooling the case makes the case able to absorb more heat (and radiate less heat). But cooling surroundings does not increase an items ability to radiate more heat. Far as I know the only way to make an item radiate more heat is to make the item hotter.
This is a long way around to say that cooling the case by 15 degrees does not make the inside of the case 15 degrees cooler. And the stuff you're trying to cool, the hard drive and CPU (ie), may not be one degree cooler, if any.
Measuring the cases temp is not an indicator of what is happening inside the case.
Brings us to convection, air currents inside the case. Moving air through the case is where benefit would be realized. Particurarly air movement through the case in the areas of heat sensitive components. Fart as I can see simply shooting air on the bottom of the case is not going to accomplish this.
Not to say mounting fans under a platform is wholly a bad idea. If the fans were mounted a d sealed to the laptop case in such a manner as to assist in feeding air to the inlets and fan, and to assist in air extraction from the outflow vents, I think that would make a real difference. Building an inclined holder with cut outs and fans is what I plan to do with this laptop.
Darn, just occured to me I could have simply said: Take a house fan, point it at your desktop PC, how much difference do you thin k it's making.? Same theory.
I looked through the Cool thingies website. I may have missed their hard data stating actual measurements of component temperatures with and without their gizmos. I hate to say lack of evidence is evidence, but I think if these things made an actual difference in the operating temps of the actual components they would be touting it. Instead I think they are allowing perception and intuitive reasoning do their marketing for them.
I look at this laptop and I am amazed. I think I couldn't fit the 320 gig HD from the PC in this thing even with the drive stuck into the lid. but they fit a 500 gig inside. Somehow. Same with the mother board. Makes for a nice wrist warmer.