On the contrary.
I love such stuff. Illusions help us see the extent of our senses.
One awesome video about illusions:
http://www.ted.com/talks/beau_lotto_...ow_we_see.html
And of course, if you want to make practical use of it - just start a salesletter with the above gibberish text style. Instant attention winning trick. Should definitely improve your response rates.