In my experience nearly all American aircrew have excellent knowledge of the AIM definitions of turbulence. When flying in America I have noticed that their aircrew are far more communicative about ride reports. Also their ATC are actively interested and consequently warn subsequent aircraft early on, providing an excellent service. As a Brit having flown lots on both sides I find their attitude of actively pursuing the smoothest ride very commendable. I imagine it may be puzzling to them why we don't talk about it quite as much. You're right Wino, it is a different mentality.