And that is one reason I am surprised at some so-called "knowledgable" pros who brag about theirhandheld feather-weight cameras with very long lenses!
I have always taught my students thatmore mass= less shake, especially with telephoto. And that is what makes the Canon 20D, for example and IMHO,FAR superior toits lightweight kin (Rebel, etc.). And I alsolike the heavyweight Sony DSC=F828; all in one and rock steady ... my "always-with-me-and-ready-in-an-instant" shooter.
In fact, I even use about 12 pounds of weights on my astronomical 8" SC telescope especially when taking photos ... the extra mass, besides acting as counterbalcance to the camera, reduces a heck of a lot of vibration.