Not to change this lovely TP discussion you guys are having, but I joined the high tech clothing crowd a few years back myself. I agree with the sentiment about it largely depends on how much you sweat/perspire, either due to physical exertion or whatever reason. If you just sit and ride, without perspiring, then just dress warm in thick layers with whatever you want to wear. it really won't matter for you IMO.
But if you do perspire, then using layers of high performance clothing, where some layers can be removed is the ticket. The clothing will also remove the water/perspiration away from your body. This helps keep you warm, which is the point. Because if you get cold or wet, fatigue will start earlier and for me anyways, that is less fun.