I couldn't agree more with the original post. In enroute airspace I regularly come across pilots who choose not to fly their cleared speed with no good reason and with plenty of notice to plan a clean descent at that speed. American based carriers never cease to amaze me at their ability to fly speed restrictions incredibly accurately. French crews also seem to be particularly good at it in my experience, as do the Spanish. These guys show us all what is fly-able and put some of their British colleagues to shame in my opinion.