sorry, i reread and now i understand what you meant. i disagree with that.
preventing a string that is not-secured from written somewhere because the same string is secured elsewhere makes it possible to detect the existance of a secured string. that is what i see as a danger and like to avoid.
seperating secured and non-secured strings should (i hope) prevent that. and to reiterate, my point is that _if_ a secured and a non-secured string are unrelated then having one version of it in swap (or written out with %O) can't do any harm. but that is a big if, since for any secured string there will always be a non-secured copy at least for some time until the string is being secured (and the non-secured version dereferenced)
greetings, martin.