A more accurate title would be 'MSL: A Lisp-like stream-based data format for history of text based on a hierarchical key-value store'.
The idea behind the format is that analysis can be done on it to uncover useful insights about the text.
The idea behind the format is that analysis can be done on it to uncover useful insights about the text.
Look, it's all S-expressions, and Lisp is certainly better than XSLT/XPath, so, sure. But there's a whole ecosystem around XML for this sort of usage that there isn't for Lisp. OTOH, Lisp is a general purpose language that lets you build DSLs as needed, so there's that advantage.