robinson-fisher - two states vs three states

[Clint Adams]

> to reclassify the words in it with, say, the S classification to move the 
> words.  Now you have not only the possibility of needing to -S the words in 
> a misdelivered spam, you might also want to -s the message.  It depends, 
> completely, on whether the message was previously classified as spam or 
> unknown.  So you have doubled the retraining complexity.

In theory, this could be simplified by a wrapper or built-in support to
evaluate the -p header.