This is probably true, but at least one implication of what the program in the title does is edit your existing comments with something before marking them as deleted, because at some point (this is probably no longer true) Reddit did not store your entire comment history.

There are obviously ways to defeat this in analysis, but it does make Reddit's job slightly harder if they want to leverage that data. It would also probably be interesting to also just edit them and not delete them in some cases in some randomized way, which would make it even harder to reliably tease out good comments from noise.