Interesting link about how we read words.
http://www.dudefree.com/Miscellany/cambridge.phpAccording to a researcher at Cambridge University, it doesn't matter in what order the letters in a word are, the only important thing is that the first and last letter be at the right place. The rest can be a total mess and you can still read it without problem. This is because the human mind does not read every letter by itself but the word as a whole.It appears that you need the correct letters as well as properly placing the first and last letter. I also think "without problem" is optimistic.

Tihs mkas it eiaser, I tnhik, to utnredsnad how slpinelg is sdcorenay to btoh rdenaig and wtrniig. I amsuse tihs is ture olny for navtie srepekas and not wehn riadneg fegiorn lguaagens. Nweer mrembes who dn'ot rbeememr Hicteh pisotng wthiuot spelccelhk may not uasnetrndd the ttile.