Much of the controversy surrounding the BritCheck has stemmed from confusing the two matters. EdLand is intimately familiar with achievement testing, but instructional screening is a foreign notion.
Google definition: screening and you'll find: the evaluation or investigation of something as part of a methodical survey, to assess suitability for a particular role or purpose.
The "something" in this case is "reading instruction"--not kids or teachers. The purpose is to identify students at the end of Yr 1 who need further instruction in how to handle the Alphabetic Code [Phonics]. Few would contend that such a methodological survey is not "a good idea." The Brit government was careful to avoid using the term, "Test," terming the instrument a "Check," but given the unfamiliarity with screening, the distinction didn't register in most quarters.
The Framework specs for the instrument are in part arbitrary--2 sections, 40 items, half words and half pseudo words. This is in keeping with the arbitrary origin of other commonplace measures http://elearning101.org/education/how-t ... ame-to-be/. The logic for wider use of the BritCheck rather than inventing some other measure, is that the invention that has already been done is "good enough" for screening purposes. Moreover, the five years of experience in using the Check in England provides valuable "evidence" on which to build.
The closest analog to the BritCheck I can think of is the Snellen Eye Chart. There are many other ways to measure visual acuity, but the Snellen check is quick and clean, and is "good enough" for screening purposes. No one would "teach to the chart," contend that young children shouldn't be exposed to it, object that it doesn't improve vision, and so on. Only in EdLand do we get tangled up in such confusion.