From a Facebook conversation with Dan Everett (about slide rules, aka slipsticks, no less) and others:

The constant revision and consequent redefining and renaming of concepts – some imaginary and some very obvious – has led to a multi-dimensional spectrum of heresy in generative grammar, so complex that one practically needs chromatography to distinguish variants. Babel comes to mind, and also Windows™ versions. Most of the literature is incomprehensible in consequence – or simply repetitive, except it’s too much trouble to tell which.