In the wake of Sts60's post, I'll stress that there is a right way to approach suspicion. Which is to say, it's not per se unreasonable for a layman to look at a network of fine tubes and believe that pushing a fluid through them might be problematic. It's generally true that the smaller and finer a conduit, the greater the force needed to achieve fluid flow in it. It's also generally true that the more convolutions, the greater the force. So these are not unreasonable suspicions. And those are the right questions to ask: How much tubing? How narrow? What did the pump look like? Taking the answers from those questions to a conclusion of feasibility is a daunting analytical task; in practice we just test, even though computations would yield a usable result. So at the bottom line is the same ultimatum as Sts60 proposed: will there be computation, or just handwaving "It wouldn't have worked!" in our future?
It's a legitimate challenge. We have people tell us the computer only at 16,000 words of storage and offering the unsubstantiated judgment that this was too small. We have people in this very forum telling us that 210 cubic feet is too small for a manned spacecraft's crew compartment. It's just elaborate question-begging. Getting the facts right isn't the same as getting the interpretation of those facts right. I always chuckle when I pass heavy construction equipment. Why? Because I think of how conspiracy theorists tell us the flexible space suit would have ballooned up under the 3.5 PSI difference in pressure, then I see rubber hydraulic hoses carrying around 3,000 PSI (standard industrial hydraulic pressure) without ballooning up. There really is no substitute for knowing the relevant facts and properties.
But forestalling all of that quantitative discussion is the qualitative nature of the LCG development. ILC (or maybe it was Hamilton Standard, since this would have been their part of the EMU) got put in the hot seat to fix the astronaut heating problem. It was a serious hot seat: "Fix the problem in two weeks or you lose the contract." Now to an engineer, that deadline means there's no time to engineer, build, and test something. Fierce deadlines means you buy a ready-made solution from someone else who has already solved a similar problem. And that's what they did. The LCG concept was nabbed from the British, who had already developed and tested it for some other purpose. They ordered one, put it on a guy, wrapped him up in plastic, and put him on a treadmill to see whether it would pull away his body heat. It did, so they just incorporated that product into the design.
That origin outside NASA makes it hard to argue that the LCG is an example of "suspicious" NASA engineering. It already existed. And its ubiquitous use in space operations for the past few decades makes it harder to argue that it's bogus.
