If you need to cause glitches in a few precisely chosen moments in time, while _not_ causing glitches in some other moments in time between the former, it gets a lot harder. It gets even harder if the response to a wrong sequence of glitches is to brick the processor / erase storage.

There are also known reasonably good defenses against glitches in PC that involve checking at every end of a basic block that a subset of instructions of this block has executed.