I think, while teaching basic mechanics, we have to be concerned with testing students' learning and motivation - otherwise we will have to celebrate IYP-2005, again, for popularizing physics among students and society. That is why I became worried about contrasting answers given by engineering students on the questions on circular motion, as reported by John Warren, Brunel, UK, in 1971.
I contributed a Letter in Physics Education, UK, in March 1984 and also repeated that point while commenting on the article of Carl Wieman in the CHANGE, May-June 2008, p. 5,
We should also remember the statement of E.E. Witmer and A.V. Bushkovitch in American Physics Teacher, August 1937. According to them, in many branches of physics, a completely logical presentation is not possible because of the incompleteness of our present knowledge. In brief, the views of Witmer, Bushkovitch and Sciama are very similar.
This seems to be true in the light of Frank Wilczek's comment (Physics Today, October 2004) who had maximum difficulty in learning classical mechanics. That is why I am pointing (in my lectures also) that although Frank Wilczek remained in physics - in spite of those difficulties and won the Nobel Prize, there could be many more Franks who left physics due to the same difficulties.
So we, teachers, have to restudy physics so as to make it logically more perfect and avoid losses of bright students and the necessity of re-celebrating another Einstein Year. I am looking forward to your response.