One way of avoiding "little lies", identified by Donald, is NOT to try
to explain everything. Some explanations are very demanding in terms of
prerequisites. "Why is the speed of light in water less than in air but
more than in glass?" or "why some molecules rotate linearly polarized
light?" are good examples. A way of dealing with such topics is to say
that "these are experimental facts to accept. Explanations are possible
but not at our level of learning." This is the best way (IMHO) to implement
the "less is more" idea in teaching physics. Naturally, a teacher should
try to explain as much as reasonably possible at every level of learning
to prevent a degeneration of physics into factology.
A physics textbook written along these lines would be a a very useful
contribution at this time. Something similar to the admirable "A First
Course in Physics" of Millikan and Gale (1906) but based on modern issues
and technology.
Ludwik Kowalski
P.S.
Who was that philosopher who said ...? something like --> "I do not
have to understand the chemistry of digestion to enjoy a good meal"?