This is just a quick and rough test showing some different methods of obscuring letters. @Tosche_e claimed that the 3rd example should be the most legible for Japanese…
Update:
I received feedback from a Japanese designer that he could easily read each of the above examples. However, this is entirely contextually based – the text is a logical sentence. Seen alone, many words may be difficult or impossible to make out. He then provided some interesting samples of how it can be impossible to identify certain obscured Kanji characters.
