Scale construction, continued

For psychometrics fans: I helped out with a post by Brent Roberts, "Yes or No 2.0: Are Likert scales always preferable to dichotomous rating scales?" This post is a continuation of our earlier conversation on scale construction and continues to examine the question of if – and if so, when – it's appropriate to use a Likert scale vs. a dichotomous scale. Spoiler: in some circumstances it's totally safe, while in others it is a disaster!