I'd be interested to know what temperatures you all are brewing at. I just tried this experiment with our house espresso (a four bean post roast blend roasted to 450-455) and again with a single origin, Ethiopia Aricha Lot 1 (roasted about 430) and I can't say that I agree at all. I tried both bottomless and spouted portafilters and our crema is thick and sweet. While I wouldn't want to taste just the crema, our espresso without it is not as delicious. So I thought, what's going on? I'm preparing espresso at 7200 feet above sea level and it occurred to me that closer to sea level most of you are probably brewing at much higher temps, like Schomer says. Here, water boils at 199 degrees, thus we brew our coffee and espresso around 194-5. In general, I think this lends to a softer profile. I'd love for somebody with a PID down at sea level to do this experiment and tell me what the difference in crema taste is between my temps (194, 20g double) and whatever you are preparing for your customers daily. I'm looking forward to doing more research on elevation and espresso/roasting (we've got almost 20% less oxygen too!) and will keep everyone posted as I learn about the effects.