I think this issue keeps coming up because of the posed peppered moth photographs in biology textbooks, and I think it has more to do with unrealistic expectations than with anything else. Photographs in textbooks are for illustration purposes. A section on predator and prey may show a leopard prepared to pounce when the reality is that the leopard was at the San Diego zoo and was just preparing to get up. That is not misrepresentation but illustration. The biology textbook's purpose is not to present firsthand evidence, but to convey information in the best way possible, and picture's do that very effectively.
A section on camouflage might describe how a chameleon protects itself along side pictures of a chameleon first gray on a leaf and then green on the same leaf. It makes no difference that the chameleon was actually placed on the leaf by an attendant at the reptile barn of a local zoo. The purpose is to illustrate camouflage, not to present evidence for a research paper.
It turns out that peppered moth predation is too complex to properly analyze in the wild (see my book review at
Book Review: Of Moths and Men), so we may never know what really happens, but there is no doubt in anyone's mind, Creationist or evolutionist, that camouflage provides a survival advantage and thereby contributes to natural selection, and this is all the textbook is trying to communicate with peppered moth photographs. The photographs aren't supposed to be from actual researchers or journal papers - they're for illustration and pedagogical purposes.
While the specifics of peppered moth predation remain elusive, and so we cannot even be sure that predation is the cause of the color changes, that the populations tend toward light and dark in response to environmental factors is very well established.
--Percy