Just to reiterate that point, there's a study in the rheumatology literature, where they took a trainee, with a US machine and compared to an experienced rheumatologist using clinical exam, and the trainee actually had better accuracy with doing joint aspiration and injections, then the experienced rheumatologist did, so if you have the clinical skills of Matt Dawson, then and an US machine, you'll be pretty much unstoppable. 