Yep, only in the case of runs of 1s - since that’s the predominant case when typing.
Runs with other difference values show up when typing in multi-cursor mode in vscode and other editors, but I haven’t optimised my data structure for that use case.
reversibly transforming a data sequence into a more easily compressible one of the same size (sometimes called 'whitening' or 'predicting') is a very general technique for data compression, and first differences are a very commonly used transformation here. others include the burrows–wheeler transform, paeth prediction, and linear predictive coding
Runs with other difference values show up when typing in multi-cursor mode in vscode and other editors, but I haven’t optimised my data structure for that use case.