Can CONFUSE be actually made with blocks following the rules?

[alchimystic]

Issue on page "ABC Problem":

I was implementing a solution in Scala (a simpler/smaller one) and according to my test, CONFUSE cannot be made with these blocks (and the rule for removing a block once one of its letters is used).
Very simply, as F and S belong to the same block, we cannot build works with both of those letters