Well, it's a lot easier as a homebrewer to say, "I think it's done, but since I'm not 100% sure, I'll just let it sit another week." Pros can't do that. I do agree that we probably dawdle too much at times, especially if you know you have a large, healthy amount of yeast, proper aeration, and control of your fermentation temps. If you're not convinced you have control of those factors, continue dawdling.