Something along those lines must have been uttered when the company Under Armour was started. I've known this business for quite some time as they've been around for a while in the US. They've unfortunately only recently come to Europe. I still won't buy there stuff here as its outrageously expensive in Euros considering I regularly buy their products on sale in Dollars, but I am still glad to see them over here. I swear by their stuff for my workouts, be it in summer or winter, indoors or out. I have no idea why but the stuff is extremely comfortable, well made (for now) and I just like the brand.
Now Under Armour has even gone into the shoe business. I guess though this is what I like the most. They are not Nike and they had the balls to take on Nike (and Adidas). It's like using Open Source because it's not Microsoft. This is a classic marketing story. Instead of being number 1, be number 2 or 3 for the people who don't want to be associated with number 1. If you're really good, you overtake number 1 for yourself (see Google).
Nevertheless, you have to differentiate yourself. Under Armour took advantage of compression clothing (now already being copied...see Skins). Make it tight and body hugging. Those just starting out their workout are highly unlikely to start wearing your clothes from day 1. It's something to strive for though. I sure know when I've again put on the pounds as I start looking more like a sausage in the compression shirts than an athlete from their website. All I do is go into the loose fitting stuff until I get back to my competitive weight.
If the stuff really helps technically, who knows? There are some studies you can follow up on via the Skins website but I highly doubt there is any real benefit for anyone but professional athletes. That's not what it's all about though...it's the marketing and perception. This has nothing to do with technology but the fact is that similar opportunities are available in the technology sector as well and many success stories started out like this. Think about it!